Evolution of The Beetles

[ericmurphy]

Your model -
1. There is an original group of Brown Beetles that can interbreed.
Funny thing, Magellan, but my model makes no mention of "Brown beetles." You seem to be having a hard time keeping your unworkable model and my model separate.


2. Their children are all different in all sorts of ways.
Just as in the real world, where no child is exactly identical to its parents.


3. So now we have a group (the next generation ) where every individual is different to their parents and different to every other individual. I assume we can still say that each individual has the capacity to interbreed with all other individuals in the group.

You "assume"? Still? You're still not sure? How many times have you actually read my explanation of my model, Magellan? Because there's really no ambiguity about which beetles can interbreed with which other beetles. Why do you need to "assume" anything?


I'll call the children of the original group the 'Second generation'.

Where is this "second generation," Magellan? Are they the "second generation" in population A? Population B? Or are we still talking about the ancestral population X? Do you know? Do you think it matters?


A question about this second generation -
Well, until you can tell me where this "second generation" is, there's probably not much to be said about it.


Can we say they are any closer to splitting, dividing into two non-interbreeding groups?
I don't know, Magellan. Is this "second generation" part of the original ancestral group X, in which all members can interbreed? Is it part of population A or population B? Because if it's part of either A or B, it's already part of two non-interbreeding groups:

http://www.planet-deepblu.com/~eric/graphic_links/Isolation.png

But in any event, whether it's a member of X or A or B, the fact that eventually you end up with two non-interbreeding groups has nothing to do with any differences in any of these organisms.

Is that point of my model still unclear to you? That the original population does not split into two non-interbreeding groups due to any differences in any of its members?


Have the differences in the second generation made any difference as far as speciating goes?

Let's see if we can try this again:

The differences between any two consecutive generations are too small to be of any significance with respect to speciation.

Maybe after a few hundred more repetitions of this:

http://www.planet-deepblu.com/~eric/graphic_links/Intergeneration.png

You'll get that.


(You mightn't have realised it - but in reality this is how reproduction works - individual by individual, couple by couple, generation by generation. So it's central to any model. )

You might not have realized it, but speciation takes hundreds of thousands of generations, and the differences between any two generations is imperceptible.

I truly hope, Magellan, that you're just trolling, and pretending to be this unteachable. (Which is still fine with me; you still make creationists look really, really bad). Because if you really are this dense, I feel really, really bad for you.

[ericmurphy]

No.
That would be assuming things.
Eric wants me to consider his model. That's what I am doing.
I understand there is a group of Brown Beetles.
If there is a split - there must be a cause.

This is why we will never, ever get to the point of my actually having to provide evidence that my model reflects reality, Magellan. You will never get to the point of understanding my model well enough even to see if it reflects reality.

The second sentence of my explanation of my model explains the cause of the splitting into two subpopulations, Magellan. It has nothing to do with any changes in any of these organisms. I suggest you go re-read my explanation again, and find out what causes the split into two subpopulations.

Faid isn't "assuming" anything.

[ericmurphy]

Oh, and before you make any more wrong claims about my gradient:

http://www.planet-deepblu.com/~eric/graphic_links/Intergeneration.png

Here's two rows of pixels from that gradient, magnified in Photoshop 1,500%:

http://www.planet-deepblu.com/~eric/graphic_links/Intergenerationzoom.png

Tell me if you see any difference in two adjacent columns of pixels.

[ericmurphy]

Since Magellan seems to be having trouble understanding the distinction between two organisms which cannot interbreed because they're too different genetically and two organisms which simply don't interbreed, maybe I can give him a couple of examples:


Whales and mice don't interbreed because they're two different genetically and morphologically; it's impossible both genetically and anatomically.

The woman who works in the office next to mine and I probably could interbreed. We certainly have similar enough genomes. But we don't interbreed because there is a barrier between us; in our case, a social barrier rather than a geographic barrier (for one thing, she's married; for another, it's verging on being illegal in the U.S. for two people who work together to have any kind of romantic relationship).

In the first instance, interbreeding is physically impossible, and would be even if the two organisms found themselves in the same environment. In the second instance, even though interbreeding is physically possible, it does not happen, for reasons that have nothing to do with genetic incompatibility.

(Cue TS jumping in with some lame attempt at humor at my expense having something to do with my social life, and Magellan jumping in with some irrelevancy about wild animals not having jobs or marriages.)

[Sparko]

Hey Magellan my good sir, do you mind me calling this MY HOUSE, since it is your thread, we brothers right?

Sparko needs to just shut up I would say, hes an embarrassment.

-Pwner of N00bs

You just got back from a two week vacation, and you are already starting with the flaming? Are you in your manic phase or what?

I see another vacation in your future if you don't calm down.

[ericmurphy]

Did Theostudent actually get banned from TWeb?

Isn't that kind of hard to do?

[Sparko]

Did Theostudent actually get banned from TWeb?

Isn't that kind of hard to do?

He seems dedicated to the task.

[Theostudent]

You just got back from a two week vacation, and you are already starting with the flaming? Are you in your manic phase or what?

I see another vacation in your future if you don't calm down.

You calm down sir, here this might help;


http://www.youtube.com/watch?v=CD2LRROpph0

[Theostudent]

He seems dedicated to the task.

Calm down Bacon Boy.

[Sparko]

Calm down Bacon Boy.
I am not the one who came in here ranting and raving like a drugged up maniac. You are.

You are just pwning yourself, Theo. I like you when you are not acting like a jerk, which seems to happen all too often. Then you come back and apologize. then do it again.

Break the cycle.

[Theostudent]

I am not the one who came in here ranting and raving like a drugged up maniac. You are.

You are just pwning yourself, Theo. I like you when you are not acting like a jerk, which seems to happen all too often. Then you come back and apologize. then do it again.

Break the cycle.

Did you eat your bacon today Captain Redbeard?

[magellan004]

And just in case you try to confuse things, this barrier simply PREVENTS the two groups from interbreeding. It doesn't mean the two groups are too different to interbreed already.

Two groups of animals and a barrier between them.
OK.
We don't know whether they used to all be able to interbreed with each other.
All we know is they cannot interbreed.

Whales and mice cannot interbreed.
We know that.
Some people say they are related. There is no reason to think that. They are separate. They cannot interbreed - as in Eric's model.

What is that supposed to show?

Magellan

[magellan004]

Until now, Mags, you were perfectly fine with having two different groups of beetles from the beginning, before speciation took place. In fact, you used that in your own scenarios repeatedly. Remember those beetles that moved to the mainland etc?

Why the sudden change?

Are you running out of obfuscations and diversions?

My model, that started with one group, was crap, ludicrous, unreal etc.

Let me know when you work out what story your model tells.
At the moment what your model says is that there are two separate groups.


'In my model there are two groups therefore speciation happens.'



Magellan

[ericmurphy]

Two groups of animals and a barrier between them.
OK.
We don't know whether they used to all be able to interbreed with each other.
All we know is they cannot interbreed.

Yes we do. Read my model again, Magellan. We start with a single ancestral population X, of freely-interbreeding organisms.


Whales and mice cannot interbreed.
We know that.
Some people say they are related. There is no reason to think that. They are separate. They cannot interbreed - as in Eric's model.

Uh, no. Whales and mice are not the result of a single speciation event.



What is that supposed to show?

It's not going to show you anything until actually understand my model. Which by all appearances is not going to happen any time soon.

[ericmurphy]

My model, that started with one group, was crap, ludicrous, unreal etc.

Yes, it was, because it did not have any of the conditions necessary for speciation to occur. Principle among them: no reproductive isolation.


Let me know when you work out what story your model tells.
Let me know when you work out the story my model tells. I know exactly what story my model tells. But you cannot, or will not, understand it.


At the moment what your model says is that there are two separate groups.

It's always said that, from the very beginning:


One ancestral population of freely-interbreeding organisms: X
An event or process that results in the splitting of X into two reproductively-isolated populations
Two isolated subpopulations of freely-interbreeding organisms: A and B




'In my model there are two groups therefore speciation happens.'

If that's all you've gotten out of my model after weeks of explanations, illustrations, and diagrams, then you truly are hopeless.

Are you hopeless, Magellan? Or are you just trolling? For your sake I'm hoping the latter, because if you really are this flummoxed by a bog-simple model like mine, I don't know how you can function in modern society.

[ericmurphy]

Since it's clear Magellan no longer has any idea what my model is, and god knows how many pages back it is now, let me restate it for the sake of convenience:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.
Over time, genetic differences in both populations accumulate, so that the members of each population becoming increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.


This is not a "different" model, Magellan. It's the same model I've been talking about from the beginning. I'm not even restating it to help you understand it; I believe you are resistant to the notion of even trying to understand it.

I'm simply posting it so it's easy to find.

[magellan004]

Yes, it was, because it did not have any of the conditions necessary for speciation to occur. Principle among them: no reproductive isolation.


Let me know when you work out the story my model tells. I know exactly what story my model tells. But you cannot, or will not, understand it.



It's always said that, from the very beginning:


One ancestral population of freely-interbreeding organisms: X
An event or process that results in the splitting of X into two reproductively-isolated populations
Two isolated subpopulations of freely-interbreeding organisms: A and B




If that's all you've gotten out of my model after weeks of explanations, illustrations, and diagrams, then you truly are hopeless.

Are you hopeless, Magellan? Or are you just trolling? For your sake I'm hoping the latter, because if you really are this flummoxed by a bog-simple model like mine, I don't know how you can function in modern society.

I don't understand your model.
It doesn't tell me any story about what happened.
It relates no history.
It seems to assumes things happened.
There doesn't seem to be any step by step process.

Could it be programmed in a computer?
Does it have a starting set of conditions?
Does it have a starting point?
Does it have rules?
Does it have events?
How do things interact?
How are formulae arrived at?
What are the formulae?
What triggers a formula?
What comparisons are made?
What entities are identified?
How are they identified?

If you can't answer this stuff then your model doesn't tell a story.
It's just a description of a state.
If that's what it is, if you can't explain it to me - then I am not interested.

And I am even less interested in your paranoid suspiciousness.


Magellan

[ericmurphy]

I don't understand your model.
I know that. It's not that complicated of a model, and I've explained it eight ways from Sunday. It's not like we're discussing Minkowski spacetimes, or Wile's proof of Fermat's last theorem. It's actually pretty simple. I guess you'll just have to give up in defeat.


It doesn't tell me any story about what happened.
Yes it does.

It relates no history.
Yes it does.

It seems to assumes things happened.
It's a model, Magellan. Do you not know what a model is?


There doesn't seem to be any step by step process.

There are eight steps I just explained in my model. Are you really saying you don't see any steps?


Could it be programmed in a computer?
It could be, and it has.


Does it have a starting set of conditions?
I gave you the starting set of conditions.


Does it have a starting point?
Try reading step one.


Does it have rules?

I gave you all the relevant rules.


Does it have events?
How do things interact?
How are formulae arrived at?
What are the formulae?

There aren't any formulae. Seriously, Magellan, I spelled the whole thing out for you in my last post. What is wrong with you? Can't you understand English? Here we are, seventy pages into this thing, and you apparently have no idea what my model is.

I really hope you're just trolling, because if you really are this stupid…


If you can't answer this stuff then your model doesn't tell a story.
It's just a description of a state.
If that's what it is, if you can't explain it to me - then I am not interested.

Read it again. And again. And again. And again. You apparently were unable to absorb a single thing from my most recent post.


And I am even less interested in your paranoid suspiciousness.

Frankly, it could not possibly matter less to me whether you're a clumsy troll or borderline mentally disabled. Either try to figure out my model, as I've spelled it out exhaustively, or bail on the thread.

Your choice.

[ericmurphy]

It's an interesting approach to trolling, anyway. Magellan gives the impression of slowly understanding more and more features of my model, and asks questions that, while not particularly intelligent, at least have something to do with the model. But then he gets to a point of frustration, where he can't really find anything objectionable about it, and at that point he goes back to pretending he doesn't understand a single thing about it.

And then we do it all over again. I don't know why he thinks it's going to go any different the next time around.

[ericmurphy]

Just for fun, let's compare my model with Magellan's "model":


t all started in Year tx with about 10 brown Beetles living on an island that had no other beetles but was very close to the mainland.
These Beetles produce children about once a year and only have one breeding season..
Each beetle has an identifier on it which shows names of its two parents and their parents etc. . This identifier system is passed on to children so the ‘first generation’ children have a record or their own parents (the tx generation) and their parent’s parents etc.

Millions of years later , in say year ty, there are 20 Beetles.
Professor Smithers Bones examines all of the Beetles There are some brown Beetles. The rest are green.
He can trace each beetle back through time.

Aside from some bogus "specifics"—first 10 beetles(!), then "millions of years later 20 beetles(!), and some completely unworkable "identifier" system (which in itself is entirely lacking in "specifics"), it looks like your "model" has rather fewer specifics than mine has, Magellan:


Some brown beetles
"millions of years"
Some brown beetles and some green beetles


And with this information, Magellan was going to instruct us in how evolutionary theory proposes speciation happens.

[magellan004]

Just for fun, let's compare my model with Magellan's "model":



Aside from some bogus "specifics"—first 10 beetles(!), then "millions of years later 20 beetles(!), and some completely unworkable "identifier" system (which in itself is entirely lacking in "specifics"), it looks like your "model" has rather fewer specifics than mine has, Magellan:


Some brown beetles
"millions of years"
Some brown beetles and some green beetles


And with this information, Magellan was going to instruct us in how evolutionary theory proposes speciation happens.

We have agreed (and I am basing this on you retaining at least partial memory) that, in my model, we have a first Gen 600 type Beetle - an individual that is different from its parents - Gen 599 type Beetes, because they couild interbreed with Group A Beetles.

As far as I am aware, we have to conclude that having the feature, the difference that this first Gen 600 Beetle has (the inability to interbreed with Group A ) means that that first Gen 600 type Beetle-
1. Cannot have Gen 599 type children and
2. No descendants of that first Beetle can have Gen 599 type Beetle children.

If that is true the the mere devenopment of a difference that causes inability to interbreed with Group A (which is an absurd proposition to start with) also means that that individual with that difference automatically cannot have children who can breed with Group A , even if their parner is a Beetle that can breed with Group A.

That's two hugely ridiculous conditions.

But that's where we are at - so let's continue.

Magellan

[ericmurphy]

We have agreed (and I am basing this on you retaining at least partial memory) that, in my model, we have a first Gen 600 type Beetle - an individual that is different from its parents - Gen 599 type Beetes, because they couild interbreed with Group A Beetles.

Magellan, I don't frankly care what your model says or does. You don't HAVE a model. You repeatedly forget that you don't even believe speciation happens. How do you have a model for something that doesn't exist?

There is one model of speciation under discussion here—mine. So no, we don't have any "agreement" about your gen-599 and gen-600 beetles. Here's another thing you've forgotten:

http://www.planet-deepblu.com/~eric/graphic_links/Intergeneration.png

and

http://www.planet-deepblu.com/~eric/graphic_links/Intergenerationzoom.png


As far as I am aware, we have to conclude that having the feature, the difference that this first Gen 600 Beetle has (the inability to interbreed with Group A ) means that that first Gen 600 type Beetle-
1. Cannot have Gen 599 type children and
2. No descendants of that first Beetle can have Gen 599 type Beetle children.

We've been through this. Neither of these statements is true. A gen-800 beetle can have a gen-599 beetle for offspring.


If that is true
It's not true, and worse, it's irrelevant for reasons that have already been explained to you repeatedly.



the the mere devenopment of a difference that causes inability to interbreed with Group A (which is an absurd proposition to start with) also means that that individual with that difference automatically cannot have children who can breed with Group A , even if their parner is a Beetle that can breed with Group A.

That's two hugely ridiculous conditions.

Neither is a condition, but even if they were—so what? Who cares if a population B beetle—any population B beetle at any point in time—is not interfertile with any population A beetle? Explain why it matters.


But that's where we are at - so let's continue.

Continue? One post ago you didn't understand a single thing about my model. You still don't understand anything about it. We can't "continue" until you at least know what my model says.

You're goin' nowhere, pal.

[magellan004]

We've been through this. Neither of these statements is true. A gen-(sic) 800 beetle can have a gen-599 beetle for offspring.

At the end there are only Gen 600 type Beetles aand Group A Beetles on the bush, unable to interbreed.

If Gen 600 type Beetles could have Gen 599 type children then we would see these types on the bush -
1. Gen 600 - unable to breed with Group A
2, Gen 599 - able to breed with Group A
3, Group A

No speciation.

Magellan

[ericmurphy]

At the end there are only Gen 600 type Beetles aand Group A Beetles on the bush, unable to interbreed.

If by "gen-600 beetles" you mean B2 beetles, beetles which cannot interbreed with population A beetles, then fine. If by "on the bush," you mean "at some point in the future where whatever was isolating the populations has been removed, so that they occupy the same ecospace," then fine.

If you mean something else, then NOT fine.


If Gen 600 type Beetles could have Gen 599 type children then we would see these types on the bush -
Why? In my model, B2 beetles are eventually the only kind of beetles there are. This has nothing to do with whether or not B2 beetles can have B1 offspring at some point in the several hundred thousand generations of isolation from population A.


1. Gen 600 - unable to breed with Group A
2, Gen 599 - able to breed with Group A
3, Group A

No speciation.

Wrong. Even in your model, there's still speciation. Group A and "gen 600" are different species. They cannot interbreed. But there's no way for that to happen in your model: there's no reproductive isolation.

In my model, which DOES have reproductive isolation, there definitely IS speciation.

I really don't care WHAT your model does, Magellan. Your model is not a model that will lead to speciation.

Mine is.

And why do you even HAVE a model? You specifically do not believe speciation happens. As I have told you before, I don't care how many bad, wrong, broken models you can come up with in which speciation does not happen. I have one model in which speciation DOES happen.

And I only need one.

[Theostudent]

After careful analysis by the Consensus of the Holy Justice League of Bad asses, we have decided to nominate Professor Smither's Bones as a Pwner of Noobs.

He has gone beyond the call of duty to make retards look like what they are, succeeding in every manner that could ever be imagined.

All in favor say; Eric is a retardo.

Welcome to the club Professor.

-Commander Shepard

[Sparko]

Dear Commode Shepturd.

Please leave this thread if you want to act like a 5-year-old

(translated into 5-year-old language for your reading comprehension)

[magellan004]

If by "gen-600 beetles" you mean B2 beetles, beetles which cannot interbreed with population A beetles, then fine. If by "on the bush," you mean "at some point in the future where whatever was isolating the populations has been removed, so that they occupy the same ecospace," then fine.

If you mean something else, then NOT fine.


Why? In my model, B2 beetles are eventually the only kind of beetles there are. This has nothing to do with whether or not B2 beetles can have B1 offspring at some point in the several hundred thousand generations of isolation from population A.



Wrong. Even in your model, there's still speciation. Group A and "gen 600" are different species. They cannot interbreed. But there's no way for that to happen in your model: there's no reproductive isolation.

In my model, which DOES have reproductive isolation, there definitely IS speciation.

I really don't care WHAT your model does, Magellan. Your model is not a model that will lead to speciation.

Mine is.

And why do you even HAVE a model? You specifically do not believe speciation happens. As I have told you before, I don't care how many bad, wrong, broken models you can come up with in which speciation does not happen. I have one model in which speciation DOES happen.

And I only need one.

The idea of a model is to examine underlying causes and results.
It doesn't matter one iota if a change that can occur takes 10 years of 1 million years.
It doesn't matter if a change that is impossible is given 10 or 1 million years to occur.

It doesn't matter how long or how many. If the model finds something that cannot happen then we can rule it out.

We are dealing with changes that occur , one generation to the next, individual by individual.

Nothing happens to a group that has not occured on an individual basis. For example , if an individual Beetle can breed with Group A then the Group that that Beetle is from cannot be said to be 'unable to interbreed'.

My model is doing nothing more than taking the evolutionists starting point - One Group of Individuals and seeing whether its possible to end up with two groups that cannot interbreed.

If it makes you feel happier then imagine we are starting off with one group of a zillion Beetles and in ten zillion years we end up with twop groups of zillions of Beetles. It will make no difference at all. The principles are the same.

So please stop pretending 'small' and 'short' is an issue. If it gives you ulcers to imagine 'two populations of Beetles on a bush' then try to imagine two massive groups of Beetes all over Africa . It won't make any difference.


Magellan

[magellan004]

Dear Commode Shepturd.

Please leave this thread if you want to act like a 5-year-old

(translated into 5-year-old language for your reading comprehension)

May I ask - when did you last give that warning to Tiggy?

Magellan

[ericmurphy]

The idea of a model is to examine underlying causes and results.
The problem, Magellan, is that you can't figure out what your own "model" predicts, and you can't even follow my model at all.


It doesn't matter one iota if a change that can occur takes 10 years of 1 million years.
It doesn't matter if a change that is impossible is given 10 or 1 million years to occur.

When you show that anything about my model is "impossible," then you'll have something. And note: claiming something is impossible is not the same thing as "demonstrating" it's impossible.


It doesn't matter how long or how many. If the model finds something that cannot happen then we can rule it out.

Lots of things can't happen in your model, Magellan. But that doesn't matter, because you can't find anything about my model that can't happen. Of course, without even a rudimentary understanding of what happens in my model, it's hard to see how you could find anything wrong with it anyway.


We are dealing with changes that occur , one generation to the next, individual by individual.

I already told you:

http://www.planet-deepblu.com/~eric/graphic_links/Intergeneration.png

One thing that's cool about "debating" you, Magellan, is I get incredible mileage out of these little graphics. I can show them to you over and over again, but you can't seem to puzzle them out.


Nothing happens to a group that has not occured on an individual basis.

Individuals don't "evolve," Magellan. Evolutionary change is an emergent phenomenon that does not happen below the population model. So you're wrong about that.


For example , if an individual Beetle can breed with Group A then the Group that that Beetle is from cannot be said to be 'unable to interbreed'.

Irrelevant. I don't say speciation has happened until all beetles in population B are unable to interbreed with population A. It's not just that they don't interbreed; beyond a certain point they can't interbreed.


My model is doing nothing more than taking the evolutionists starting point - One Group of Individuals and seeing whether its possible to end up with two groups that cannot interbreed.

And that's your problem. You have one group of individuals, with no reproductive barrier. I've told you a million times speciation will not happen under those circumstances. I've been telling you that since the beginning of this thread.

You need this:

http://www.planet-deepblu.com/~eric/graphic_links/Isolation.png


If it makes you feel happier then imagine we are starting off with one group of a zillion Beetles and in ten zillion years we end up with twop groups of zillions of Beetles. It will make no difference at all. The principles are the same.

Actually, it makes no difference above a certain population. Populations of less than one thousand individuals typically go extinct fairly quickly. Above that level it makes no difference. So stop arguing about something you can't win.


So please stop pretending 'small' and 'short' is an issue. If it gives you ulcers to imagine 'two populations of Beetles on a bush' then try to imagine two massive groups of Beetes all over Africa . It won't make any difference.

Magellan, you vastly overestimate yourself. Do you think I would waste my time making fun of someone like you if it gave me ulcers?

Your "model" is crap. I've explained exactly why it's crap. Your unrealistic numbers are the least of its problems.

My model is the one you need to worry about. If I were you, I'd be worried about my inability to comprehend it. That's your biggest problem right now.

You can't argue against a model you don't understand.

[ericmurphy]

May I ask - when did you last give that warning to Tiggy?

Magellan

Tiggy actually has something to offer. If you provoke him enough, he'll grind your arguments to pieces with data and empirical evidence you can't even understand, let alone refute.

The last time TS said something remotely relevant or interesting was weeks ago.

[ericmurphy]

Here, Magellan: read it again.




We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.
Over time, genetic differences in both populations accumulate, so that the members of each population becoming increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.


This is not a "different" model, Magellan. It's the same model I've been talking about from the beginning. I'm not even restating it to help you understand it; I believe you are resistant to the notion of even trying to understand it.

I'm simply posting it so it's easy to find.

[magellan004]

You sound like you want to turn this thread into a Duelling Banjos Model thread. You very welcome to start your own thread with your own model. Just clear it with Sparko first.



The problem, Magellan, is that you can't figure out what your own "model" predicts, and you can't even follow my model at all.

I predict that my model will show that speciation is impossible.



Lots of things can't happen in your model, Magellan. But that doesn't matter, because you can't find anything about my model that can't happen. Of course, without even a rudimentary understanding of what happens in my model, it's hard to see how you could find anything wrong with it anyway.

You are probably best to start your own Model thread. My model is simple, clear and to the point. It does something yours apparently doesn't - it shows the step-by-step processes involved in biological groups.

It uses the starting point provided by evolution and leaves nothing out - not one step is omitted.

I highly recommend it .



Individuals don't "evolve," Magellan. Evolutionary change is an emergent phenomenon that does not happen below the population model. So you're wrong about that.
That's an assertion that my model will examine.




Irrelevant. I don't say speciation has happened until all beetles in population B are unable to interbreed with population A. It's not just that they don't interbreed; beyond a certain point they can't interbreed.
When can we say that Group A has speciated?




And that's your problem. You have one group of individuals, with no reproductive barrier. I've told you a million times speciation will not happen under those circumstances. I've been telling you that since the beginning of this thread.
Gobbledygook.
You can't have one group that is in two groups.

'Here is a group , one of them is in Africa, one of them is in Norway.' < --- Incoherent.

I think what you mean is -

We start with one group.
Next Step . That group is split into two groups.



Your "model" is crap. I've explained exactly why it's crap. Your unrealistic numbers are the least of its problems.
How many times have you pretended that the numbers are an issue?

I'll say it once more - if you like, imagine we are dealing with 10,000,000,000,000 Beetles.
The principles are the same as dealing with 10, 20, 100.



My model is the one you need to worry about. If I were you, I'd be worried about my inability to comprehend it. That's your biggest problem right now.
But I am not worried about your model so it must be faulty.

Try a new thread.
You will have plenty enough to worry about with my model.
Every so often I mention the weaknesses with evolution that my model shows and those occasions correspond with the insistences that I address your model and with your defensive insults-throwing.

Magellan

[Faid]

Two groups of animals and a barrier between them.
OK.
We don't know whether they used to all be able to interbreed with each other. Yes we do. They did.

All we know is they cannot interbreed.No, they can still interbreed, that is, it would be POSSILBE for them to interbreed, if the barrier did not PREVENT them from interbreeding. That is how it all starts.

You were fine with this before. Why the sudden change?


Whales and mice cannot interbreed.
We know that.
Some people say they are related. There is no reason to think that. They are separate. They cannot interbreed - as in Eric's model.Eric's model has two interbreeding populations separated by a barrier, not two entirely different species. the members of the two groups are able to interbreed at first, then reproductive isolation (the BARRIER) separates them, and differences start to accumulate in the two populations (which will EVENTUALLY lead to speciation). Get it now?


What is that supposed to show?

Nothing. It's just squid ink on your part. At this point, we're discussing a model of speciation.

Remember: you YOURSELF agreed to a separation of the beetles in two populations BEFORE speciation. It was in your models, for crying out loud.

Where's your problem now?

[Faid]

My model, that started with one group, was crap, ludicrous, unreal etc.

Let me know when you work out what story your model tells.
At the moment what your model says is that there are two separate groups.


'In my model there are two groups therefore speciation happens.'



MagellanNonsense.

At this point, you don't even try to read what we say, you just try to avoid addressing it with incomprehensible blabber. Why don't you actually read my posts (and Eric's, and sylas', etc) and tell me HOW exactly we say anything that amounts to "Two groups, therefore speciation"? Can you display a most basic comprehension of the English language?

Or are you just too desperate to try and actually defend your position?

[Faid]

I don't understand your model.
It doesn't tell me any story about what happened.
It relates no history.
It seems to assumes things happened.
There doesn't seem to be any step by step process.

Could it be programmed in a computer?
Does it have a starting set of conditions?
Does it have a starting point?
Does it have rules?
Does it have events?
How do things interact?
How are formulae arrived at?
What are the formulae?
What triggers a formula?
What comparisons are made?
What entities are identified?
How are they identified?

If you can't answer this stuff then your model doesn't tell a story.
It's just a description of a state.
If that's what it is, if you can't explain it to me - then I am not interested.

And I am even less interested in your paranoid suspiciousness.


MagellanLOL. OK, now you ARE trolling. I guess you got advice to play the troll card to try and save face, because you're getting clobbered. "Noooo I'm not just some internet wise-ass who got pwned (as theo would say), I'm just a reaaaally smart troll see?"

Whatever, Mags. When you decide to honestly and genuinely discuss these issues, let me know.

[Sparko]

May I ask - when did you last give that warning to Tiggy?

Magellan

Don't worry, tiggy has gotten his fair share of moderations for flaming and disruption too.

[ericmurphy]

You sound like you want to turn this thread into a Duelling Banjos Model thread.
No, Magellan, that would be you. As I've said repeatedly, it makes no sense for you to be coming up with a "model" of speciation when you're specifically trying to argue that speciation cannot happen. As I've also repeatedly said, it doesn't matter how many bad, wrong, broken "models" you come up with under which speciation won't happen. I only need one under which it will happen.



I predict that my model will show that speciation is impossible.

I've already told you under your "model," speciation won't happen. I even told you why.


You are probably best to start your own Model thread. My model is simple, clear and to the point.
Your model is missing ingredients that are crucial to speciation. I could just as easily create a model in which speciation doesn't happen because there's no reproductive isolation and no mutation. How hard would that be?


It does something yours apparently doesn't - it shows the step-by-step processes involved in biological groups.

Magellan, explain how this:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.
Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.


doesn't have any steps.


It uses the starting point provided by evolution and leaves nothing out - not one step is omitted.

Oh, really? Where's the reproductive isolation, Magellan?


I highly recommend it .

Yeah—it's great for creationist sheep who want desperately to believe their comic-book view of natural history is right.


That's an assertion that my model will examine.
Your "model" doesn't "examine" anything. What does your model do, Magellan? You've got some bugs. They're all the same color. You've got some unworkable scheme that you claim lists every single ancestor of every single bug over "millions of years." And then magically you've got
two different groups of different-colored bugs which for inexplicable reasons can't interbreed.

Which, by the way, means speciation has happened.

The difference between your "model" and my model is that under my model we have an explanation for how it happened.


When can we say that Group A has spectated?

You got a problem with the English language, Magellan? I tell you speciation has happened when the beetles in population B are unable to interbreed with population A. You then ask me when speciation happened.

Or maybe you don't understand that if population B cannot interbreed with population A. I find it difficult to believe anyone could be that clueless, but I admit you've really lowered the bar on cluelessness.


Gobbledygook.
I really wish you would stop assuming that just because you can't figure out what a sentence means, that means no one can.


You can't have one group that is in two groups.

Oh, really? You've got a theater with two exits. The group of people in the theater leaves by both exits, meaning there's a group of people who left by one exit and another group of people who left by the other exit. Your objections to my model become more and more surreal every day.


'Here is a group , one of them is in Africa, one of them is in Norway.' < --- Incoherent.

Here's a group of people in Africa. Half of the people in the group moved to Norway. And according to you, that's impossible or something?


I think what you mean is -

We start with one group.
Next Step . That group is split into two groups.

Gee, Magellan, you "think" that's what I mean? You mean, something like this?



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.


Is that what you're talking about? You "think" that's what it means?


How many times have you pretended that the numbers are an issue?

I've told you repeatedly under what conditions numbers are an issue. In your "model," where the numbers YOU GAVE were "10" and "20," numbers ARE an issue. It's hardly the most significant issue, but it's still an issue.


I'll say it once more - if you like, imagine we are dealing with 10,000,000,000,000 Beetles.

Great. All in one big population. With no accumulation of mutations and no reproductive isolation.

And you wonder why speciation doesn't happen in your "model." Even after I've TOLD you why it won't happen in your "model."


The principles are the same as dealing with 10, 20, 100.

No they're not, and I've explained why they're not repeatedly.


But I am not worried about your model so it must be faulty.

Now THAT is pretty incoherent. Of course, you still don't understand my model (or at least pretend not to understand it), so your lack of worry about it doesn't carry a whole lot of credibility.


Try a new thread.

Nope. You wanted to talk about Evolution of The Beetles. That's what I'm talking about. And besides, I thought you said you weren't worried about my model?


You will have plenty enough to worry about with my model.
You don't HAVE model. What you have, general, is some sort of horrible spasm.


Every so often I mention the weaknesses with evolution that my model shows
What your model shows, Magellan, is your ignorance of how evolution works. Since evolutionary theory predicts that under the conditions of your model speciation won't happen, you're not really showing any problems with evolution, are you?


and those occasions correspond with the insistences that I address your model and with your defensive insults-throwing.

When you stop calling my statements "gobbledygook," I'll stop calling your statements evidence of cluelessness.

[Faid]

Here's a group of people in Africa. Half of the people in the group moved to Norway. And according to you, that's impossible or something?Of course not. He used the same concept himself in his models, where he was perfectly fine with beetles "moving to the mainland". His own posts show his dishonesty.

He's just desperate and he's throwing squid ink around.

[ericmurphy]

I'm curious about this "feature" of your "model," Magellan—the one you claim can trace the ancestry of each bug back an arbitrary number of generations. First, how does it work? How do you take a bug from, say, generation 537,225, and trace its ancestry back to generation 1?

Second, what does this "feature" of your "model" provide us in terms of information about how your "model" ends up with exactly what you claim can't happen: two species of bugs?

Don't you think it's a little strange that your "model," which according to you shows that speciation is impossible, actually assumes that speciation happens?

[magellan004]

Don't worry, tiggy has gotten his fair share of moderations for flaming and disruption too.

OK. Thanks.

Magellan

[magellan004]

I'm curious about this "feature" of your "model," Magellan—the one you claim can trace the ancestry of each bug back an arbitrary number of generations. First, how does it work? How do you take a bug from, say, generation 537,225, and trace its ancestry back to generation 1?
In Beetle Land all children are micro-chipped with details copied from both parents as well as information about each new difference.




Second, what does this "feature" of your "model" provide us in terms of information about how your "model" ends up with exactly what you claim can't happen: two species of bugs?
Having the ancestry detail of each Beetle means that we can trace back to any point and find out where significant events happened - for example - 'This bug couldn't interbreed with group A yet its parents could. Therefore it was these differences that it had at birth that caused that inability to interbreed.'



Don't you think it's a little strange that your "model," which according to you shows that speciation is impossible, actually assumes that speciation happens?

A gross lack of understanding such a simple concept.
' IF we were to finish up with two groups of Beetles on the one bush and those groups could not interbreed, is it possible that those two groups both had the same single group ancestry?'

It's a 'What-If?'
It's a way of seeing whether something is possible.
A means of testing a claim.
'If we were to find an American flag on the Moon, is it possible it was put there by Americans 40 years ago?'
'If we were to find a boat on Mount Sinai is it possible that it was put there by vikings?'

That doesn't mean we 'believe' the vikings put a boat on the mountain. What we think or feel has nothing to do with it. It's a way of investigating a claim.

You would make a lousy policeman. You wouldn't investigate any leads unless somehow you knew they were correct before you investigated them.

Magellan

[ericmurphy]

In Beetle Land all children are micro-chipped with details copied from both parents as well as information about each new difference.

But you can't tell us how this ludicrously-unrealistic system actually works, how it got there, or what it tells us.

Sure, I could say the same thing about my model; it not only gives us all genetic information and information about ancestors, but also gives us GPS location data recorded on a second-by-second basis as well as 720p HD video of whatever the beetle happens to be looking at during its day.

And?


Having the ancestry detail of each Beetle means that we can trace back to any point and find out where significant events happened - for example - 'This bug couldn't interbreed with group A yet its parents could. Therefore it was these differences that it had at birth that caused that inability to interbreed.'

Having a system is one thing, Magellan. Actually being able to tell something by looking at the data it supposedly produces is another. Tell me, Magellan: what does this "micro-chipped" system actually tell you? Anything?


A gross lack of understanding such a simple concept.
' IF we were to finish up with two groups of Beetles on the one bush and those groups could not interbreed, is it possible that those two groups both had the same single group ancestry?'

According to your model? No. Why not?


Because your model does not have any accumulation of mutations
Because there is no reproductive isolation between any one group of beetles and any other


I've been telling you this for seventy pages now. It's unlikely it will ever sink in.


It's a 'What-If?'
It's a way of seeing whether something is possible.
A means of testing a claim.
'If we were to find an American flag on the Moon, is it possible it was put there by Americans 40 years ago?'
'If we were to find a boat on Mount Sinai is it possible that it was put there by vikings?'

If we were to find two species of beetle on the same bush, is it possible they share a common ancestry?

Yes. And here's how:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.
Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.


Any questions? Are we done now?


That doesn't mean we 'believe' the vikings put a boat on the mountain. What we think or feel has nothing to do with it. It's a way of investigating a claim.

We've investigated the claim. I've demonstrated that it is, in fact, possible, for two species of beetle found on the same bush can indeed share the same ancestry. And you've been manifestly unable to explain why my model is unworkable. By contrast, I've been able to explain exactly why your model is unworkable.


You would make a lousy policeman. You wouldn't investigate any leads unless somehow you knew they were correct before you investigated them.

Are you talking about me, or about yourself, Magellan? You seemed quite sure my model is wrong despite being unable to understand it. If anyone is unwilling to investigate any leads, it's you, not me. I looked at your model, determined that it is unworkable—it cannot explain how two species of beetle could share a common ancestry—and proposed an alternative explanation that does show how two species of beetle can share a common ancestry.

[ericmurphy]

Still waiting for word on how Magellan's "micro-chipped" system can give us information on the ancestry of beetles in generation 537,225 all the way back to generation 1.

[magellan004]

1. We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
2. At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
3. The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.
4. Over time, genetic differences in both populations accumulate, so that the members of each population becoming increasingly different from members of the other population (but selective pressures minimize the differences within a population).
5. As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
6. After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
7. Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
8. As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.


This is not a "different" model, Magellan. It's the same model I've been talking about from the beginning. I'm not even restating it to help you understand it; I believe you are resistant to the notion of even trying to understand it.

I'm simply posting it so it's easy to find.

Good. At least you have set out some steps.

1. We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other. OK. Same as in my model.

2. At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B.[/B] At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any
OK. Makes sense.

3. The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions,
OK

3. The isolating event or process could be migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population,
No.
If the Group A individuals were all flying (or walking) to the same destination at the same time on one day (or in one year) then for some of them to fly somewhere different the next day requires some sort of cause. For example – Did some of them decide to behave differently? Were some of them instantaneously born with the same difference that makes Beetles want to migrate to a different destination, or at a different time?

Again the problem is you can’t get wholesale changes in a group without it starting with one individual. Otherwise you have mass differences appearing spontaneously.

3. The isolating event or process could be …colonization of an island by either subpopulation
No. We start with one Group – Group A, not ‘subpopulations’. If you wish to suggest sub-populations you would need to define them and state why they arose.

3. The isolating event or process could be … or even a genetic event like polyploidy or chromosomal fission or fusion.
That’s just meaningless. What on earth is ‘a genetic event’?
Why not stick to geographical separation? The environment imposes a division, not the group members. Geographic is the only way I know that a split can happen. If you want to argue that one day some members decided to secede then I think you have a new version of evolution.

None of this really matters though because we can use geographical isolation.
I’ll respond to your Step 4 as soon as I get time.

Magellan

[ericmurphy]

Good. At least you have set out some steps.

I don't know what thread you've been reading, Magellan, but my "steps" have been laid out for days now.


OK. Same as in my model.

And that's about the last thing my model and your "model" have in common.


OK. Makes sense.

Finally? You finally get the part about my model that's lacking from your "model"? The existence of a reproductive isolation of the two subpopulations?


OK

So you understand how reproductive isolation works, then?


No.
Right. That's what I was afraid of.


If the Group A individuals were all flying (or walking) to the same destination at the same time on one day (or in one year) then for some of them to fly somewhere different the next day requires some sort of cause. For example – Did some of them decide to behave differently? Were some of them instantaneously born with the same difference that makes Beetles want to migrate to a different destination, or at a different time?

Come on, Magellan; use whatever brains you have. You've got an original population of beetles in, say, South Africa. Over time, that original population spreads further north until several hundred thousand years later, it reaches all the way to sub-Saharan Africa. At this point, we now have two subpopulations that are for all intents and purposes reproductively isolated. The chances of a beetle in Botswana mating with a Beetle in Camaroon are zero.

Humans spread throughout the New World beginning roughly 30,000 years ago, reaching Tierra del Fuego roughly 8,000 years ago. What is the "difference" that made humans want to spread from north-east Asia all the way to the tip of South America? What, conversely, would prevent them from spreading, other than some sort of geographical barrier?

So what prevents the population in Camaroon from drifting apart genetically from the population in South Africa? What, indeed, prevents the population in South Africa from drifting apart genetically from its ancestors from several hundred thousand years ago?


Again the problem is you can’t get wholesale changes in a group without it starting with one individual. Otherwise you have mass differences appearing spontaneously.

Sure I can. A hundred differences per individual per generation. I don't know where you got this idea that you can only have a single individual being different per generation, but it's obviously wrong. Just because one particular mutation might arise just once in an entire population doesn't mean thousands of other mutations aren't arising at the same time in other individuals. We DO have wholesale changes in a group happening simultaneously.


No. We start with one Group – Group A, not ‘subpopulations’. If you wish to suggest sub-populations you would need to define them and state why they arose.

Read this part again, Magellan:


1. We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
2. At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.

We start out with X, not A. An isolating process or event leads to two subpopulations, A and B. I don't know why you have such an incredibly difficult time understanding this step in the process, a step that is no more difficult to understand that taking one group of a hundred people, and dividing it into two groups based on the first letter of their last name: group 1 is A through L, and group 2 is M through Z.

Why can't you figure this out? Could it be because you don't want to figure it out?


That’s just meaningless. What on earth is ‘a genetic event’?
It's cute when you say something is meaningless after I tell you what it means. I gave you two examples: polyploidy and chromosomal fission and/or fusion.


Why not stick to geographical separation? The environment imposes a division, not the group members. Geographic is the only way I know that a split can happen. If you want to argue that one day some members decided to secede then I think you have a new version of evolution.

Hey, if you want to stick with just allopatric speciation, I'm fine with that. I'm just alerting you that sympatric speciation can happen too. I only need one mechanism for reproductive isolation, but I actually have two.


None of this really matters though because we can use geographical isolation.

Well, it's nice to know that while at the beginning of your post you denied geographic isolation can happen, now you're admitting that it can happen, and it's all we need to happen.


I’ll respond to your Step 4 as soon as I get time.

Well, you haven't really responded to steps 1 through 4 yet. You've given me not even a hint of a reason to think there's anything wrong with any of them.

[ericmurphy]

Magellan's biggest problem with speciation (aside from his religious problems with it) is that he can't get past this wrong idea of his that differences have to happen in a single generation. No matter how many times it's described to him how mutations slowly accumulate in a population, he just can't seem to get his mind around the concept. And that's not the only gradual process he can't seem to understand.

Where does he get this idea that geographical isolation has to involve a whole group of beetles breaking camp and moving to another country in a single day. or even a single year? Why can't he even imagine a situation where a species' territorial range expands over tens of thousands or hundreds of thousands of years? Does he think the entire human population of North America arrived here in a single year? Even if you ignore the indigenous population, just the arrival of the European population took centuries, and is still continuing today.

[ericmurphy]

Here's another inexplicable comment from Magellan:


[My model]does something yours apparently doesn't - it shows the step-by-step processes involved in biological groups.

I wonder where it does that. Here's his "model" again:


It all started in Year tx with about 10 brown Beetles living on an island that had no other beetles but was very close to the mainland.

These Beetles produce children about once a year and only have one breeding season..
Each beetle has an identifier on it which shows names of its two parents and their parents etc. . This identifier system is passed on to children so the ‘first generation’ children have a record or their own parents (the tx generation) and their parent’s parents etc.

Millions of years later , in say year ty, there are 20 Beetles.

So what are the "steps" in Magellan's "model"?


We start with some beetles that are all the same color.
They reproduce.
After millions of years, there are some green beetles and some brown beetles.


Where, I wonder, is the description of the "step-by-step processes involved in biological groups"? The only "step" I see is beetles reproducing. How does this "step" result in some green beetles and some brown beetles? And why can't these two different colors of beetles interbreed (which, by the way, isn't even mentioned in Magellan's "model")?

[magellan004]

Come on, Magellan; use whatever brains you have. You've got an original population of beetles in, say, South Africa. Over time, that original population spreads further north until several hundred thousand years later, it reaches all the way to sub-Saharan Africa. At this point, we now have two subpopulations that are for all intents and purposes reproductively isolated. The chances of a beetle in Botswana mating with a Beetle in Camaroon are zero.

Humans spread throughout the New World beginning roughly 30,000 years ago, reaching Tierra del Fuego roughly 8,000 years ago. What is the "difference" that made humans want to spread from north-east Asia all the way to the tip of South America? What, conversely, would prevent them from spreading, other than some sort of geographical barrier?

Your reply has nothing to do with migration patterns. And it doesn't matter anyway. The changing migration patterns was just a little inaccuracy of yours.


So what prevents the population in Camaroon from drifting apart genetically from the population in South Africa? What, indeed, prevents the population in South Africa from drifting apart genetically from its ancestors from several hundred thousand years ago?

The same thing that prevents Aborigines in Western Australia and in Tasmania from drifting apart. There is something that you are not accounting for that prevents this hypothesised 'drift'.

Indeed Humans from 200,000 ago were humans and we are still humans. And we are spread all over the place.

And it's the same thing that prevents hippos from drifting apart.
I doubt that a group of hippos in one lake in Uganda will ever breed with another group of Hippos in a lake a few miles away. Yet they are all hippos, free to interbreed.



Sure I can. A hundred differences per individual per generation. I don't know where you got this idea that you can only have a single individual being different per generation, but it's obviously wrong. Just because one particular mutation might arise just once in an entire population doesn't mean thousands of other mutations aren't arising at the same time in other individuals. We DO have wholesale changes in a group happening simultaneously.

What I meant was that you can't have a group of Beetles migrating to Camaroon each year then next year several Beetles decide to break with tradition and migrate to Ibiza off the Spanish coast.

You can't have six legged Beetles one year then the next year have 100 eight legged Beetles born in the same generation. Whatever the change or difference is, it always starts with one child.

We have wholesale changes occurring all the time with Aborigines and it makes no difference. They are all still able to interbreed.

You have to show something else - a cause of lack of interbreeding ability. And that cause must start with one individual. And then you have to work out why it is a lack of ability to interbreed with some animal the parents have no contact with.

Were you the first human born with a lack of ability to mate with an Australian Aborigine? You have all the prerequisites - reproductive isolation and vast accumulation of differences. The idea is preposterous. And worse still - you then could only give birth to children who couldn't mate with Aborigines. That's the only way speciation could work.

Magellan

[ericmurphy]

Your reply has nothing to do with migration patterns.
It specifically mentions migration patterns. It gives an example of a migration pattern. What, you thought I was talking about seasonal migrations? How would that lead to reproductive isolation?

Are you even thinking?



And it doesn't matter anyway. The changing migration patterns was just a little inaccuracy of yours.

There's nothing "inaccurate" about my statement. It's a model, Magellan. I'm not talking about a specific historical migration of a specific species of beetle that actually happened. What were you saying earlier about "investigating possibilities"? Now we can only talk about events that actually happened?

Did your "brown beetles turning into green and brown beetles over millions of years" thing actually happen?




The same thing that prevents Aborigines in Western Australia and in Tasmania from drifting apart. There is something that you are not accounting for that prevents this hypothesised 'drift'.

I've accounted for it over and over again. The reason Aborigines are not drifting apart from other human populations is that a) 50,000 years is not enough time, and b) there is no current reproductive isolation between Aborigines and other populations, and hasn't been for at least several hundred years.


Indeed Humans from 200,000 ago were humans and we are still humans. And we are spread all over the place.

I already said a hundred thousand generations is a decent estimate for the time it takes for speciation assuming that length of reproductive isolation. No human population has even existed for a hundred thousand generations, let alone been isolated for that long.


And it's the same thing that prevents hippos from drifting apart.
What's this same thing, Magellan? What is it that keeps two reproductively-isolated populations from drifting apart? Whatever this "thing" is, you can't seem to figure out what it is.


I doubt that a group of hippos in one lake in Uganda will ever breed with another group of Hippos in a lake a few miles away. Yet they are all hippos, free to interbreed.

And how long have they been separated, Magellan?


What I meant was that you can't have a group of Beetles migrating to Camaroon each year then next year several Beetles decide to break with tradition and migrate to Ibiza off the Spanish coast.

Since that doesn't bear the slightest resemblance to what I'm talking about, who cares? I AM NOT TALKING ABOUT AN ANNUAL MIGRATION. Whatever gave you the idea I was talking about an annual migration. Where is the "annual migration" in this:


Over time, that original population spreads further north until several hundred thousand years later, it reaches all the way to sub-Saharan Africa. At this point, we now have two subpopulations that are for all intents and purposes reproductively isolated. The chances of a beetle in Botswana mating with a Beetle in Camaroon are zero.

I'm talking about an extension in a population's range over several hundred thousand generations. I'm not talking about a population of beetles in Botswana taking an annual holiday in Camaroon.

It's simply amazing the weird misconceptions you have about how things work in the real world.


You can't have six legged Beetles one year then the next year have 100 eight legged Beetles born in the same generation. Whatever the change or difference is, it always starts with one child.

Still stuck on the idea of immense change happening in a single generation. Still can't get your mind around this:

http://www.planet-deepblu.com/~eric/graphic_links/Intergeneration.png


We have wholesale changes occurring all the time with Aborigines and it makes no difference. They are all still able to interbreed.

There are no "wholesale changes" occurring in Aboriginal populations. Humans as a species have extremely low diversity; much lower than can be found in a single troupe of chimps. Worse—for you—there is no reproductive isolation separating Aborigines from other humans. Humans have not been around long enough as a species to see any speciation.


You have to show something else - a cause of lack of interbreeding ability.
I already have:

http://www.planet-deepblu.com/~eric/graphic_links/InterfertilityVsDifferences.png

—resulting in:

http://www.planet-deepblu.com/~eric/graphic_links/GeneticDriftV2.png

Stop pretending I haven't shown things I've already shown, repeatedly.


And that cause must start with one individual. And then you have to work out why it is a lack of ability to interbreed with some animal the parents have no contact with.

No. Wrong. A single mutation might, or might not, start with a single individual—and you haven't even constructed an argument as to why that's true. As for a whole slew of mutational differences—a hundred or so per individual per generation don't start with a single individual.

Stop repeating this falsehood, Magellan. You can't make a false statement true through endless repetition.


Were you the first human born with a lack of ability to mate with an Australian Aborigine?
I'm sure there have always been humans unable to mate with any Aborigines; or any humans, for that matter. Sterile humans are born all the time. And there were definitely people born after the "first person unable to mate with an Australian Aborigine" who were able to mate with Aborigines.

No wonder you don't think speciation can happen, with all these incredibly wrong and inaccurate ideas about how even reproduction works.


You have all the prerequisites -
No we don't.


reproductive isolation and vast accumulation of differences.
and no we don't. No human population has been isolated for more than a few thousand generations at most. Humans have very low diversity. There is no "vast accumulation of differences." You're just making this stuff up.


The idea is preposterous.
YOUR ideas certainly are preposterous.


And worse still - you then could only give birth to children who couldn't mate with Aborigines.
Wrong. There is nothing to prevent a beetle in population B2 from giving birth to a beetle that is in population B1. Nothing whatsoever.


That's the only way speciation could work.

No it's not.

There. I obliterated—once again—every single objection to my model you've made. I can keep doing this until doomsday.

[ericmurphy]

I wonder how many times Magellan is going to repeat his example of Australian aborigines, who were isolated from other human populations for at most a few tens of thousands of years, when i keep telling him you need at least a hundred thousand generations for a complete lack of interfertility.

Maybe Magellan doesn't realize that a human generation is more than one year.

I'm also interested in what happened to his claim that there is more genetic difference between Australian Aborigines and Africans than there is between modern humans and H. erectus populations from a million years ago.

[ericmurphy]

For those interested (which presumably does not include Magellan), here's a link to a paper discussing the observed low genetic diversity in humans:

http://www.pnas.org/content/106/1/33.full.pdf+html

[magellan004]

I wonder how many times Magellan is going to repeat his example of Australian aborigines, who were isolated from other human populations for at most a few tens of thousands of years, when i keep telling him you need at least a hundred thousand generations for a complete lack of interfertility.

Maybe Magellan doesn't realize that a human generation is more than one year.

I'm also interested in what happened to his claim that there is more genetic difference between Australian Aborigines and Africans than there is between modern humans and H. erectus populations from a million years ago.

We went through this with the Beetles. Time is irrelevant. There has to be a change, a difference that causes an inability to interbreed.

My claim that there is more genetic difference between Australian Aborigines and Africans than there is between modern humans and H. erectus populations from a million years ago was backed up with mathematics based on figures you had given for mutations in human children. It is always going to be the case that the differences between a family line will be less than the differences between neighbours in a group. There is less difference between you and your Mayflower ancestors than there is between you and your neighbour next door.

Anyway - back to this 'accumulated differences takes lots of time ' thing.

I'll use Americans and Aborigines. Use Beetles if you wish. Also feel free to add any number of zeros to the years. The principle is the same.

1. Your 200,000th grand ancestor could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.
2. Your 199,999th grand ancestor could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.
3. Your 199,998th grand ancestor could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.
...
4. Your grandmother could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.
5. Your father could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.

...

7. Your 199,998th grand descendant couldn't interbreed with Aborigines. If he/she were transported to Australia they could not have had 'American'/Aboriginal child.
8. Your 199,999h grand descendant couldn't interbreed with Aborigines. If he/she were transported to Australia they could not have had 'American'/Aboriginal child.

So something happened in between step 5 and Step 7.

Step 6 - Eric was born different to his parents in a way that robbed him of the ability to interbreed with Aborigines.

And this necessarily means that Eric and his descendants cannot have children that can interbreed with Australian Aborigines. You have formed a separate Species. The ability to interbreed has gone. If you could have children that could interbreed with Aborigines than there would be no Speciation.

So - this difference that you were born with has a double effect -
1. It makes you unable to interbreed with animals you have had no contact with and
2. It prevents you from having children that have the same abilities that your parents had. Even if your children mate with people who can interbreed with Aborigines , that ability gets lost in any children .

This amazing double combuxtion of properties only happens to you - not to your group - and it is only passed down through your family line.

And amazingly, (as shown in the Beetle example) all ordinary humans (who can mate with other humans , in your group, get wiped out.

Quite a combuxtion, I must say.

Magellan

[ericmurphy]

We went through this with the Beetles. Time is irrelevant.
No it's NOT "irrelevant." I have told you over and over and over again that speciation is a process that takes hundreds of thousands of generations. It does NOT happen in a single generation.


There has to be a change, a difference that causes an inability to interbreed.

Wrong. You keep insisting that there has to be a change. No. There are typically millions of changes that cause an inability to interbreed. Humans and chimps differ in tens of millions of nucleotides, not a single nucleotide.

Once more for the terminally clueless:

http://www.planet-deepblu.com/~eric/graphic_links/InterfertilityVsDifferences.png


My claim that there is more genetic difference between Australian Aborigines and Africans than there is between modern humans and H. erectus populations from a million years ago was backed up with mathematics based on figures you had given for mutations in human children.
No it's not. You have NO IDEA how many differences there are in humans compared to how many there are between H. sapiens and H. erectus. But simple mathematics shows that there are many more differences in organisms 2 million years apart than in organisms 100,000 years apart. Your claim collapses on those grounds alone.

Seriously, Magellan: how can there be more generations between now and 100,000 years ago and now and two million years ago.


It is always going to be the case that the differences between a family line will be less than the differences between neighbours in a group. There is less difference between you and your Mayflower ancestors than there is between you and your neighbour next door.

Really? Even if your next-door neighbor is your sister? Do you even THINK before you post these inanities?


Anyway - back to this 'accumulated differences takes lots of time ' thing.

I'll use Americans and Aborigines. Use Beetles if you wish. Also feel free to add any number of zeros to the years. The principle is the same.

1. Your 200,000th grand ancestor could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.
Aborigines didn't exist 200,000 generations ago. EPIC FAIL.


2. Your 199,999th grand ancestor could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.
3. Your 199,998th grand ancestor could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.
...
4. Your grandmother could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.
5. Your father could interbreed with Aborigines. If he/she were transported to Australia they could have had 'American'/Aboriginal child.


Any human who has ever existed could interbreed with Aborigines. You can't figure out why?


So something happened in between step 5 and Step 7.

NOTHING happened. 50,000 years is not nearly enough time to achieve an elimination of interfertility.


Step 6 - Eric was born different to his parents in a way that robbed him of the ability to interbreed with Aborigines.

And this necessarily means that Eric and his descendants cannot have children that can interbreed with Australian Aborigines. You have formed a separate Species. The ability to interbreed has gone. If you could have children that could interbreed with Aborigines than there would be no Speciation.

So - this difference that you were born with has a double effect -
1. It makes you unable to interbreed with animals you have had no contact with and
2. It prevents you from having children that have the same abilities that your parents had. Even if your children mate with people who can interbreed with Aborigines , that ability gets lost in any children .

This amazing double combuxtion of properties only happens to you - not to your group - and it is only passed down through your family line.

What is this stupidity, Magellan? Are you drunk? THERE HAS NOT BEEN ENOUGH TIME SINCE ABORIGINES FIRST ARRIVED IN AUSTRALIA FOR THEM TO BECOME UNABLE TO INTERBREED WITH OTHER HUMANS. It is pointless to even TALK about a lack of interfertility among human populations, because HUMANS HAVE NOT EXISTED LONG ENOUGH AS A SPECIES for there to be speciation.


And amazingly, (as shown in the Beetle example) all ordinary humans (who can mate with other humans , in your group, get wiped out.

Quite a combuxtion, I must say.

You haven't learned a single thing since the beginning of this thread 71 pages ago. When your entire argument is this easy to shred, it's really time to just give up.

[ericmurphy]

Magellan simultaneously claims time is "irrelevant," and then talks about Aborigines being reproductively isolated for 50,000 years.

He clearly wants to have his cake and eat it, too.

[magellan004]

Really? Even if your next-door neighbor is your sister? Do you even THINK before you post these inanities?

That howler was in reponse to ' It is always going to be the case that the differences between a family line will be less than the differences between neighbours in a group.'

I've got some startling news for you - your sister is in your family line. My sister is in my family line.

Perhaps you need to think before you rush to the keyboard.

Magellan

[ericmurphy]

That howler was in reponse to ' It is always going to be the case that the differences between a family line will be less than the differences between neighbours in a group.'

I've got some startling news for you - your sister is in your family line. My sister is in my family line.


Really? Is your sister your ancestor, Magellan? I suppose that's possible—certainly more possible than having eight grandparents—but it would be in the nature of one of those deep dark family secrets which wouldn't normally be disclosed even to complete strangers.

Perhaps you need to think before you rush to the keyboard.

And while you're doing that, maybe you can explain your reasoning for how the differences between, say, me and someone living in Lyons, France, will be much greater than the differences between me and a specimen of Homo erectus who lived 1.7 million years ago.

[ericmurphy]

And if you still think the genetic diversity among modern humans mean they must be more different from each other today than they are from their distant ancestors a million and a half years ago, maybe you'd like to read this:

http://www.pnas.org/content/106/1/33.full.pdf+html

[ericmurphy]

Here's some more figures for you, Magellan, if you think humans have enough genetic diversity to have speciated in the last 200,000 years. This figure is a raw calculation based on the number of generations, the number of mutations/generation, and the size of the genome (and hence will not necessarily agree with the figures in the link I provided you):

Years: 200,000
Generation length: 20 yrs
Generations: 10,000
Mutations/generation: 150
Total mutations: 1,500,000
Genome size (bp): 3,000,000,000
Percent difference: 0.05%

Based on these raw calculations, humans should be 99.95% identical.

If you think that's enough difference for speciation, then why do you have such a hard time believing speciation is possible, Magellan?

[magellan004]

Here's some more figures for you, Magellan, if you think humans have enough genetic diversity to have speciated in the last 200,000 years. This figure is a raw calculation based on the number of generations, the number of mutations/generation, and the size of the genome (and hence will not necessarily agree with the figures in the link I provided you):

Years: 200,000
Generation length: 20 yrs
Generations: 10,000
Mutations/generation: 150
Total mutations: 1,500,000
Genome size (bp): 3,000,000,000
Percent difference: 0.05%

Based on these raw calculations, humans should be 99.95% identical.

That's very similar to my calculation. A descendant is 0.05% different to its early ancestor.
With neighbours (those not in the family line) it's a different calculation.

In the first generation two neighbours are at least (absolute minimum conservative average) 320 mutations apart. So over 10,000 generations those differences magnify.

The percent difference is small for family lines compared to differences between members of the same generation.

Magellan

[magellan004]

Here's some more figures for you, Magellan, if you think humans have enough genetic diversity to have speciated in the last 200,000 years. This figure is a raw calculation based on the number of generations, the number of mutations/generation, and the size of the genome (and hence will not necessarily agree with the figures in the link I provided you):

Years: 200,000
Generation length: 20 yrs
Generations: 10,000
Mutations/generation: 150
Total mutations: 1,500,000
Genome size (bp): 3,000,000,000
Percent difference: 0.05%

Based on these raw calculations, humans should be 99.95% identical.

If you think that's enough difference for speciation, then why do you have such a hard time believing speciation is possible, Magellan?

Let's say we write a computer program to simulate the things we are talking about -
1. A group of animals freely interbreeding.
2. Children have differences to their parents.
3. Something causes the group to split into two groups.
4. Later, after a certain time has elapsed, the two groups are brought back together.

How might the computer program determine whether the two groups can interbreed?

Magellan

[Faid]

That's very similar to my calculation. A descendant is 0.05% different to its early ancestor.
With neighbours (those not in the family line) it's a different calculation.

In the first generation two neighbours are at least (absolute minimum conservative average) 320 mutations apart. So over 10,000 generations those differences magnify.

The percent difference is small for family lines compared to differences between members of the same generation.

MagellanUm, mags, members of the same generation INTERBREED to produce the next generation. I'll let you figure out what that means.

[Faid]

Funny how Mags kept telling us that "time is irelevant" until now, and now he's trying to base his entire anti-speciation 'argument' on time.

[sylas]

Let's say we write a computer program to simulate the things we are talking about -
1. A group of animals freely interbreeding.
2. Children have differences to their parents.
3. Something causes the group to split into two groups.
4. Later, after a certain time has elapsed, the two groups are brought back together.

How might the computer program determine whether the two groups can interbreed?


Repeating what has been said before, many times, for anyone reading who might be a tad slow on the uptake.

A computer program can represent certain aspects of biology, which we already know exist, and show some simple consequences that follow.

Key points.

Differences accumulate, from generation to generation. This happens quite inevitably if you have a program to make small random differences with each generation. It also happens in biology.
Within a breeding population, any small random difference that arises will eventually either spread through the entire population, or else become eliminated from the population. This has the force of a mathematical theorem if there is no selection involved, or if there is a simple selection for or against the change. Population genetics is the study of how changes (mutations) become either fixed or eliminated in populations over time. You don't need to program this explicitly; it happens quite automatically with heritable change.
When there is too much difference between individuals, they have a significantly reduced or even totally absent capacity to breed a new generation. This is a plain biological reality, and can easily be represented in a model where fertility simply degrades with increasing genetic distance.


Put these things in a computer simulation, and you will inevitably get "speciation" when two populations are artificially separated and prevented from interbreeding (corresponding to the simple case of geographical isolation), and you run the simulation long enough for the populations to diverge sufficiently far that individuals no longer breed between populations even if the geographical separation is removed.

This is a bog simple model. It can't be "refuted" by inventing a completely different model having nothing to do with actual biology and refuting that. (A bizarre tactic taken by Magellan when he invents his own alternative models rather than deal with models that actually correspond to biology and evolution.)

Got it yet? Of course not. I am on the edge of my seat to see how you can distort or misunderstand this next time.

Magellan -- if you decide not to BELIEVE in evolution, that's your prerogative. All I'm doing is explaining existing basic concepts in biology; not trying to prove them. But your attempts to disprove them, or show that it can't work, have been uniformly ridiculous.

Cheers -- sylas

[ericmurphy]

That's very similar to my calculation. A descendant is 0.05% different to its early ancestor.
With neighbours (those not in the family line) it's a different calculation.

And what might that calculation be, Magellan? And why does it matter? Where is your evidence that the genetic diversity between living humans is greater than the difference between living humans and, say, living chimps?


In the first generation two neighbours are at least (absolute minimum conservative average) 320 mutations apart. So over 10,000 generations those differences magnify.

No they don't. Selection pressures within a freely-interbreeding population prevent too much divergence in genome; members which are so different genetically as to have reduced fertility are eliminated from the gene pool. We've been through this already.

What are the selection pressures that keep a population from diverging over time from an ancestral population, Magellan? Do you think modern humans are at a selective disadvantage because they can't interbreed with their ancestors from four million years ago?


The percent difference is small for family lines compared to differences between members of the same generation.

Really? So modern humans have more genetic diversity than they have differences from their primitive amniote ancestors from 300 million years ago?

You still haven't found a single problem with my model.

[ericmurphy]

I wonder what Magellan thinks a "family line" even is, given he thinks his sister is in his family line (I'm assuming that he's mistaken about what "family line" means, and not that his sister really is one of his ancestors).

Also, it's pretty entertaining that Magellan would talk about how high the genetic diversity is in living humans after I like to a paper that discusses how low the genetic diversity of living humans is.

[magellan004]

Repeating what has been said before, many times, for anyone reading who might be a tad slow on the uptake.

A computer program can represent certain aspects of biology, which we already know exist, and show some simple consequences that follow.

Key points.

Differences accumulate, from generation to generation. This happens quite inevitably if you have a program to make small random differences with each generation. It also happens in biology.
Within a breeding population, any small random difference that arises will eventually either spread through the entire population, or else become eliminated from the population. This has the force of a mathematical theorem if there is no selection involved, or if there is a simple selection for or against the change. Population genetics is the study of how changes (mutations) become either fixed or eliminated in populations over time. You don't need to program this explicitly; it happens quite automatically with heritable change.
When there is too much difference between individuals, they have a significantly reduced or even totally absent capacity to breed a new generation. This is a plain biological reality, and can easily be represented in a model where fertility simply degrades with increasing genetic distance.


Put these things in a computer simulation, and you will inevitably get "speciation" when two populations are artificially separated and prevented from interbreeding (corresponding to the simple case of geographical isolation), and you run the simulation long enough for the populations to diverge sufficiently far that individuals no longer breed between populations even if the geographical separation is removed.

This is a bog simple model. It can't be "refuted" by inventing a completely different model having nothing to do with actual biology and refuting that. (A bizarre tactic taken by Magellan when he invents his own alternative models rather than deal with models that actually correspond to biology and evolution.)

Got it yet? Of course not. I am on the edge of my seat to see how you can distort or misunderstand this next time.

Magellan -- if you decide not to BELIEVE in evolution, that's your prerogative. All I'm doing is explaining existing basic concepts in biology; not trying to prove them. But your attempts to disprove them, or show that it can't work, have been uniformly ridiculous.

Cheers -- sylas

You don't know what you are talking about.

Magellan

[magellan004]

Um, mags, members of the same generation INTERBREED to produce the next generation. I'll let you figure out what that means.

No they don't.

Some do. Some don't. Aborigines in Western Australia did not interbreed with Tasmanian Aborigines.

Magellan

[ericmurphy]

You don't know what you are talking about.

Magellan

You, who know absolutely nothing about evolutionary theory, or how computer simulations of that theory would work, have no idea whether or not sylas knows what he's talking about.

I do know something about evolutionary theory, and about how computer simulations of it would work, and I can say with high confidence that sylas does know what he's talking about.

Come on, Magellan. You've already admitted you can't even follow my incredibly simple, bare-bones model for how speciation happens. If you can't follow my model, how on earth would you be able to comprehend a fully-worked-out computer simulation of the same process?

[ericmurphy]

No they don't.

Really? Then where does the next generation come from, if it's not from the prior generation interbreeding to produce it?


Some do. Some don't. Aborigines in Western Australia did not interbreed with Tasmanian Aborigines.

Oh, really? You're claiming that no Australian aborigines ever interbreed with Tasmanian aborigines? Are you claiming that Australian aborigines are unable to interbreed with Tasmanian aborigines?

You must have been really overtired when you wrote this.

And still no response about the demonstrated low genetic diversity among living humans. But then, Magellan's completely run out of objections, ludicrous or otherwise, to my model.

[magellan004]

And what might that calculation be, Magellan? And why does it matter? Where is your evidence that the genetic diversity between living humans is greater than the difference between living humans and, say, living chimps? N

No they don't. Selection pressures within a freely-interbreeding population prevent too much divergence in genome; members which are so different genetically as to have reduced fertility are eliminated from the gene pool. We've been through this already.

What are the selection pressures that keep a population from diverging over time from an ancestral population, Magellan? Do you think modern humans are at a selective disadvantage because they can't interbreed with their ancestors from four million years ago?
The calculation is -
Husband, wife, child
The child must necessarily have less differences to its parents than husband does to wife.
The grandchild must have less differences to its grandparents than the differences between all the grandparents. And therefore there are many, many more differences between a grandchild and it's (say) school friends than between that grandchild and its grandparents.


The evidence is in the mathematics. This is simply based on the figures you provided for mutations in children.
It matters because you say that accumulation of differences causes lack of interbreeding ability.
If that is true, and if 'common ancestor' is true (which it looks like it isn't) then any of your Species would be much more capable of mating with their common ancestor than they would with some living members of their own species.



Really? So modern humans have more genetic diversity than they have differences from their primitive amniote ancestors from 300 million years ago?
Yes - Sort of .
Ancestor Amniote- Living descendant A, Living descendant B.
All A's and B's would be closer to the ancestor than to some other living A's and B's.

Hey - that's evolution. That's your Gig. The common ancestor thing obviously has hairs on it.


You still haven't found a single problem with my model.
The problem is similar to watching a magician on stage.
He shows you the lady about to be sawn in half. He covers her up with a curtain. Tells us to wait. Uncovers her and shows that she's chopped in half.
We never know what happened during the missing time period.

It's not an analysis. It's like you presenting an article about how little diversity there is between 'hominids'. Those idiots are not looking at whether evolution happens. They are assuming evolution. And they are assuming the smoke and mirrors processes are real. (That's what sylas does). There's no ability to examine the consequences of their theory. Its more a constant process of patching up the holes.

This is a classic example- 'Selection pressures weed out those with reduced fertility.'
There is no reason to think that. Speciation depends on reduced fertility. There is nothing to prevent children being born with increased fertility - able to interbreed with animals that the parents could not interbreed with. But that would play havoc with Speciation so we can't consider that.

Magellan

[Faid]

No they don't.

Some do. Some don't. Aborigines in Western Australia did not interbreed with Tasmanian Aborigines.

MagellanLOL. Is that supposed to be an argument?

"Individuals whithin the same group interbreed"

"Not if there are two different groups they don't!"


Mags, within a non-reproductively isolated population, do individuals of the same generation interbreed to produce the next generation, or don't they?

[Faid]

The calculation is -
Husband, wife, child
The child must necessarily have less differences to its parents than husband does to wife.
The grandchild must have less differences to its grandparents than the differences between all the grandparents. And therefore there are many, many more differences between a grandchild and it's (say) school friends than between that grandchild and its grandparents.


The evidence is in the mathematics. This is simply based on the figures you provided for mutations in children.
It matters because you say that accumulation of differences causes lack of interbreeding ability.
If that is true, and if 'common ancestor' is true (which it looks like it isn't) then any of your Species would be much more capable of mating with their common ancestor than they would with some living members of their own species.


Yes - Sort of .
Ancestor Amniote- Living descendant A, Living descendant B.
All A's and B's would be closer to the ancestor than to some other living A's and B's.

Hey - that's evolution. That's your Gig. The common ancestor thing obviously has hairs on it.


The problem is similar to watching a magician on stage.
He shows you the lady about to be sawn in half. He covers her up with a curtain. Tells us to wait. Uncovers her and shows that she's chopped in half.
We never know what happened during the missing time period.

It's not an analysis. It's like you presenting an article about how little diversity there is between 'hominids'. Those idiots are not looking at whether evolution happens. They are assuming evolution. And they are assuming the smoke and mirrors processes are real. (That's what sylas does). There's no ability to examine the consequences of their theory. Its more a constant process of patching up the holes.

This is a classic example- 'Selection pressures weed out those with reduced fertility.'
There is no reason to think that. Speciation depends on reduced fertility. There is nothing to prevent children being born with increased fertility - able to interbreed with animals that the parents could not interbreed with. But that would play havoc with Speciation so we can't consider that.

Magellan

^^^^ Notice how Mags now completely disrgards the concept of reproductive isolation as a cause in speciation.

[ericmurphy]

The calculation is -
Husband, wife, child
The child must necessarily have less differences to its parents than husband does to wife.
The grandchild must have less differences to its grandparents than the differences between all the grandparents. And therefore there are many, many more differences between a grandchild and it's (say) school friends than between that grandchild and its grandparents.

First, that's not a "calculation," it's a claim, and second, it's based on nothing at all, not even the hint of an argument. And besides, comparing the differences between two people whose common ancestor might have lived a thousand generations ago and someone whose common ancestors lived one generation ago doesn't exactly help your argument.


The evidence is in the mathematics.
There is no "mathematics." I don't know what you think "mathematics" means, but typically it has something to do with numbers. I don't see any numbers involved in your claim at all.


This is simply based on the figures you provided for mutations in children.
It's not based on anything at all. That a child has more genetic similarities to its mother than its mother has to its father does your "argument," whatever it turns out to be once you make it, absolutely no good at all.

I think we can all agree that two individuals whose common ancestor lived a thousand generations ago are probably going to be more different genetically than two individuals whose common ancestor lived one generation ago. How does that show speciation is "impossible"?


It matters because you say that accumulation of differences causes lack of interbreeding ability.
Between reproductively-isolated populations, moron. How many times does this need to be explained to you? No living humans are members of reproductively-isolated populations.



If that is true, and if 'common ancestor' is true (which it looks like it isn't) then any of your Species would be much more capable of mating with their common ancestor than they would with some living members of their own species.

No it's not, because you keep freaking forgetting about reproductive isolation. Selection pressures do not operate to prevent interfertility losses between isolated populations. They DO operate to prevent it within a population.



Yes - Sort of .
No. Not even remotely. To even claim they do is borderline-retarded.


Ancestor Amniote- Living descendant A, Living descendant B.
All A's and B's would be closer to the ancestor than to some other living A's and B's.

Than some other living As and Bs that are vastly more closely related than either is to a fantastically-remote ancestor from a third of a billion years ago? Are you saying two humans are more different from each other than either is from a chicken? Is that really your claim?

You stink of desperation, Magellan.


Hey - that's evolution. That's your Gig. The common ancestor thing obviously has hairs on it.

No. Your bad, wrong, stupid, broken misinterpretation of common ancestry has hairballs all over it.


The problem is similar to watching a magician on stage.
He shows you the lady about to be sawn in half. He covers her up with a curtain. Tells us to wait. Uncovers her and shows that she's chopped in half.
We never know what happened during the missing time period.

Right. Except for the extensive fossil record made up of millions of fossils, plus the terabytes of genetic data we have of living organisms. Aside from that, we don't know anything.


It's not an analysis.
It's a model. You're supposed to be analyzing that model and figuring it out if it is a plausible explanation for speciation. But since you cannot seem to understand the model at all, despite its fantastic simplicity, you are unable to analyze it at all.


It's like you presenting an article about how little diversity there is between 'hominids'.

I didn't present an article about how little diversity there is between "hominids." I presented an article about how little diversity there is among living humans. You either didn't read the paper, or you couldn't figure out what it was talking about.


Those idiots are not looking at whether evolution happens. They are assuming evolution.
Those "idiots"—who are astronomically smarter than you are—aren't "assuming" anything. They're measuring genetic diversity among various human populations, and from that inferring patterns of migration through time.

It's always funny when you, of all people, denigrate the intelligence of others.


And they are assuming the smoke and mirrors processes are real. (That's what sylas does).
There's nothing "smoke and mirrors" about DNA analysis, Magellan. It's used in courtrooms all the time to either convict or exonerate accused murderers, and to determine with fantastically high accuracy whether someone is the father of a child.


There's no ability to examine the consequences of their theory. Its more a constant process of patching up the holes.

Says the guy who doesn't have even the vaguest notion what evolutionary theory says. Who cannot for the life of him understand what "reproductive isolation" means.

Who hasn't a clue about anything.


This is a classic example- 'Selection pressures weed out those with reduced fertility.' [/quote


Like there's no evidence for selection pressures. Where do you think antibiotic or pesticide resistance comes from? Magic?

[quote]There is no reason to think that.
There's no reason for YOU to think that, because you're not smart enough to follow even simple arguments.


Speciation depends on reduced fertility. There is nothing to prevent children being born with increased fertility - able to interbreed with animals that the parents could not interbreed with. But that would play havoc with Speciation so we can't consider that.

We do consider it, and it doesn't have any effect on theories of speciation, as I've explained to you countless times.

It's entertaining watching how irritable you get when you see your claims crumbling, Magellan. You just lash out at everything and everyone.

[ericmurphy]

Magellan needs to get this graphic tattooed on his forehead:

http://www.planet-deepblu.com/~eric/graphic_links/Isolation.png

[magellan004]

LOL. Is that supposed to be an argument?

"Individuals whithin the same group interbreed"

"Not if there are two different groups they don't!"


Mags, within a non-reproductively isolated population, do individuals of the same generation interbreed to produce the next generation, or don't they?
Short term memory loss?


Um, mags, members of the same generation INTERBREED to produce the next generation.
No they don't.
Some do , some don't. Members of generation x in Western Australia did not interbreed with members of generation x in Tasmania.

And to save time, some members of a group interbreed, some don't. You're implied argument depends on every animal in a group regularly interbreeding with every other animal in the group; and - here's where it falls apart - any animal not in the ancestor's line dying off - not producing descendants. 'The ancestor' = the one with the interbreeding disability.


Magellan

[ericmurphy]

Short term memory loss?

Seriously, Magellan: posts like this make you come off as borderline-retarded. But on the wrong side of the border.

Individuals within a reproductively-isolated population interbreed to form the next generation of that population. They do NOT interbreed with other populations. At all.


No they don't.
Seriously. How stupid do you have to be to make a claim like this? If members of the same generation DON'T interbreed to form the next population, then where does that population come from?


Some do , some don't. Members of generation x in Western Australia did not interbreed with members of generation x in Tasmania.

There is no reproductive isolation between Western Australia and Tasmania. Just because there was tens of thousands of years ago does not mean there is today.

Are you daft?

Maybe you think Faid is saying everyone in Western Australia interbreeds with everyone in Tasmania? Is that what you think he's saying?


And to save time, some members of a group interbreed, some don't.
Says the guy who has been maintaining that interfertility is either 100% or 0. Your brain is so rotted you can't even keep track of your own claims.


You're implied argument depends on every animal in a group regularly interbreeding with every other animal in the group;
It depends on no such thing, but you're so used to mischaracterizing and misrepresenting everyone else's arguments you don't even realize you're doing it anymore.


and - here's where it falls apart - any animal not in the ancestor's line dying off - not producing descendants. 'The ancestor' = the one with the interbreeding disability.

Uh, no.

Wow. Hard to believe anyone could be this utterly, thoroughly, comprehensively lost. No wonder you don't think evolution is true. You're not smart enough to realize it's true.

[magellan004]

Ancestor Amniote- Living descendant A, Living descendant B.
All A's and B's would be closer to the ancestor than to some other living A's and B's.


Than some other living As and Bs that are vastly more closely related than either is to a fantastically-remote ancestor from a third of a billion years ago? Are you saying two humans are more different from each other than either is from a chicken? Is that really your claim?

No.
There's no way you could deduct that from what I said .
But you might simply not be able to grasp what I said, so I'll assist -

Ancestor Amniote, living Chicken, living Human.
Amniote & Chicken - close,
Amniot & human - close,
Chicken and Human - distant.

Think of a very broad, flattened triangle.

I hope that helps.
(Don't quote me. This stuff is based on your maths and your evolution. It's screwy but I'm just here to show the absurd consequences of your theory.}

Magellan

[ericmurphy]

No.
Then what is your claim? It seems to be that any two randomly-chosen currently-living human beings are more different genetically than a modern human and a primitive amniote from 300 million years ago are.

Which is obvious stupidity.


There's no way you could deduct that from what I said .
It's impossible to deduce, not "deduct," anything rational from what you said.


But you might simply not be able to grasp what I said, so I'll assist -

There's nothing to "grasp" from utter hogwash.


Ancestor Amniote, living Chicken, living Human.
Amniote & Chicken - close,
Amniot & human - close,
Chicken and Human - distant.

Still wrong. A modern chicken and a modern human are more closely related than either one is to a 300-million-year-old amniote. Of course, you wouldn't know this, because you don't know anything about common descent, genetics, biology, or science, for that matter.

So you think you and your first cousin are more distantly related than either of you are to an ancestor from five thousand years ago? Can you really be that utterly clueless? Is it possible for a human being to be that utterly clueless?


Think of a very broad, flattened triangle.

I hope that helps.
Of course it doesn't "help." None of your bad, wrong, broken, incorrect "information" helps. You can't get "help" from the congenitally clueless.


(Don't quote me. This stuff is based on your maths and your evolution. It's screwy but I'm just here to show the absurd consequences of your theory.}

It's not based on anything. It's based on your own hallucinations about what you think you know.

So: you're batting zero with finding anything wrong or implausible about my model of how speciation happens. So why, again, do you not think speciation happens? Other than that you think anything scientists think is wrong?

[ericmurphy]

These two:

http://www.hollywood-celebrity-pictures.com/Celebrities/Olsen-Twins/Olsen-Twins-1.JPG

—are genetically more different from each other than either is from this:

http://upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Proterogyrinus_DB.jpg/150px-Proterogyrinus_DB.jpg

—according to Magellan, not according to evolutionary theory.

[shunyadragon]

I would like to introduce you to The Beetles. These little guys are going to walk us through a hypothetical simulation of evolution.

It all started in Year tx with about 10 brown Beetles living on an island that had no other beetles but was very close to the mainland.
These Beetles produce children about once a year and only have one breeding season..
Each beetle has an identifier on it which shows names of its two parents and their parents etc. . This identifier system is passed on to children so the ‘first generation’ children have a record or their own parents (the tx generation) and their parent’s parents etc.

Millions of years later , in say year ty, there are 20 Beetles.
Professor Smithers Bones examines all of the Beetles There are some brown Beetles. The rest are green.
He can trace each beetle back through time.

But something puzzles the good Professor- Have these Beetles evolved and are there different 'Species' of Beetles?

Any ideas how we might answer these questions?


Magellan

Just a comment. Insufficient information concerning the beetles and their genetic makeup. Color is an insufficient criteria if not meaningless characteristic for defining a new species. The professor needs to determine if the green beetles will breed normally with the brown beetles. What is the genetic make of the two groups of beetles?

[magellan004]

Still wrong. A modern chicken and a modern human are more closely related than either one is to a 300-million-year-old amniote. Of course, you wouldn't know this, because you don't know anything about common descent, genetics, biology, or science, for that matter.

So you think you and your first cousin are more distantly related than either of you are to an ancestor from five thousand years ago?

Magellan: 2 + 2 = 4
Eric : Still wrong.
Eric : So you still think 2 + 2 = 5?

I'll say it again for the mentally impaired -
Amniote , Chicken, Human
Amniote and Chicken - relatively few differences
Amniote and Human - relatively few differences
Human and Chicken - relatively many differences.


Magellan

[ericmurphy]

Magellan: 2 + 2 = 4
Eric : Still wrong.
Eric : So you still think 2 + 2 = 5?

I'll say it again for the mentally impaired -
Amniote , Chicken, Human
Amniote and Chicken - relatively few differences
Amniote and Human - relatively few differences
Human and Chicken - relatively many differences.


Magellan

No matter how many times you repeat this, you're still claiming 2 + 2 = 5.

Primitive amniote and chicken: huge number of differences
Primitive amniote and human: huge number of differences.
Human and chicken: large number of differences.

Of course, now Magellan has removed the term "primitive" from his characterization of "amniote," which results in his shooting himself in the head with his sidearm since both humans and chickens are amniotes, and therefore the comparison is meaningless. It's like he's saying a German shepherd is closer to a collie than it is to a dog.

Not that any of this helps Magellan in any way, shape, or form. He still can't figure out my incredibly basic, simple model well enough to even frame a coherent criticism of it, so instead he tries (and fails) to make some completely bogus, retarded argument that currently-extant organisms always have more genetic differences between them than either of them do with a distant, hundreds-of-millions-of-years-ago ancestor.

He simply radiates desperation. He's given up even the pretense of actually addressing my model.

[sylas]

... A modern chicken and a modern human are more closely related than either one is to a 300-million-year-old amniote. [...]

Eric, how do you conclude this?

A simple measure of closeness of relationship of two individuals is the total number of generations for each individual to their most recent common ancestor; this is also going to correlate will with the degree of genetic difference. I'd expect more difference between chicken and human than between either one and a common ancestor 300 million years ago.

Roughly twice as much difference, in fact, since the chicken and human lineages have been diverging for most of the 300 million years; and so there is approaching 600 million years worth of accumulated difference between the two lineages.

Cheers -- sylas

[magellan004]

Just a comment. Insufficient information concerning the beetles and their genetic makeup. Color is an insufficient criteria if not meaningless characteristic for defining a new species. The professor needs to determine if the green beetles will breed normally with the brown beetles. What is the genetic make of the two groups of beetles?

Hello and welcome to the discussion.
The 'Brown Beetles' and 'Green Beetles' was merely a way of saying 'Here are two types of Beetles'. My use of colours has caused confusion. Think of the color as a way of saying Type A Beetles and Type B Beetles - they are different in some way.

Your question about 'What features do we use to identify whether two types of Beetles can interbreed ?' is really what the thread is about. Do we assume there are two Species then look for reasons why they can't interbreed or do we find out if they can't interbreed then look for reasons?

As Sylas and others have pointed out several times - we can have different species that can interbreed. So using the label 'Species' is meaningless - unless - we agree that Species means one thing - a classification of animal that can interbreed but that cannot interbreed with other kinds types of animals.

Much of the discussion in the thread has been about this -

IF Smithers Bones observes that the two types of Beetles (Green and Brown) cannot interbreed then, according to evolution, is it possible that the two types of Beetles originated from the one original group?

I'm not sure that I agree with you about needing more 'genetic information' since the hypothesis of evolution was once not dependant on genetic information. Smithers Bones has access to historical and genealogical information.

Magellan

[sylas]

As Sylas and others have pointed out several times - we can have different species that can interbreed. So using the label 'Species' is meaningless - unless - we agree that Species means one thing - a classification of animal that can interbreed but that cannot interbreed with other kinds types of animals.


The correct conclusion is definitely not that the label species is meaningless.

First, to repeat what I was ACTUALLY pointing out: the biological species definition is NOT simply based on the notion of "cannot interbreed".

Here -- yet again -- is the definition of the biological species definition provided at the Evolution 101 website, page on Biological Species Concept (http://evolution.berkeley.edu/evosite/evo101/VA1BioSpeciesConcept.shtml). (See also msg #946 where I look at some of the additional subtleties in biology and the barriers to interbreeding, going a bit beyond the simple "can't interbreed" notion.)
The biological species concept defines a species as members of populations that actually or potentially interbreed in nature, not according to similarity of appearance. Although appearance is helpful in identifying species, it does not define species.

There's more at that page, and in the post #946 I link above. The point is that the real biological species concept is given in terms of cohesive groups which DO NOT interbreed, rather than CAN NOT interbreed; and this can occur for a whole range of reasons. That you can, in artificial circumstances, get viable cross breeds is not actually in conflict with the definition.

But whether you use the biological definition, or a more simple definition involving "can not interbreed", you will still get, inevitably, gray areas during a speciation process where separation into two species is not simply resolved as a binary yes/no conclusion. Simple binary yes/no classifications don't match observed biological realities.

To mix this up with the notion of the definition being "meaningless" is flatly wrong.

Cheers -- sylas

[ericmurphy]

Eric, how do you conclude this?

Because humans and chickens share a common ancestor that is more recent than the ancestor they share with a primitive amniote.


A simple measure of closeness of relationship of two individuals is the total number of generations for each individual to their most recent common ancestor; this is also going to correlate will with the degree of genetic difference. I'd expect more difference between chicken and human than between either one and a common ancestor 300 million years ago.

Why? They have a more recent common ancestor than either one does with a stem-group amniote. By your own reasoning (which is the same as mine) they are more closely related than either is to a stem-group amniote.


Roughly twice as much difference, in fact, since the chicken and human lineages have been diverging for most of the 300 million years; and so there is approaching 600 million years worth of accumulated difference between the two lineages.

I don't think so. But to know for sure, you'd have to know how much difference there is between the earliest amniotes (which is what I'm talking about, not, as Magellan apparently is, any old amniote which would of course include living mammals and birds) and the last common ancestor of synapsids and sauropsids. Given the murkiness of that part of the phylogenetic tree, I don't think any firm estimates can be made, although I think it's pretty safe to assume that there are a fair number of branching between the earliest amniotes and the LCA of synapsids and sauropsids.

But of course none of this is remotely relevant to a discussion of speciation. The differences between humans and chickens have been accumulating through the last several hundred million years and countless individual speciation events.

[ericmurphy]

Hello and welcome to the discussion.
The 'Brown Beetles' and 'Green Beetles' was merely a way of saying 'Here are two types of Beetles'. My use of colours has caused confusion. Think of the color as a way of saying Type A Beetles and Type B Beetles - they are different in some way.

Your question about 'What features do we use to identify whether two types of Beetles can interbreed ?' is really what the thread is about. Do we assume there are two Species then look for reasons why they can't interbreed or do we find out if they can't interbreed then look for reasons?

No. With living organisms there is no reason to "assume" they are different species. We can directly test whether they are different species. If it turns out that they are—that they can't interbreed—then my model lays out a plausible explanation for how they could have diverged from a common ancestor.


As Sylas and others have pointed out several times - we can have different species that can interbreed.
Under some definitions of the term "species." Under others, we can't.


So using the label 'Species' is meaningless - unless - we agree that Species means one thing
Just because a term can have more than one meaning does not mean it is "meaningless." There are countless words in the English language with multiple meanings. That doesn't make them meaningless.


- a classification of animal that can interbreed but that cannot interbreed with other kinds types of animals.

All organisms can interbreed with some organisms and not with others, so that definition is pretty meaningless in itself.


Much of the discussion in the thread has been about this -

IF Smithers Bones observes that the two types of Beetles (Green and Brown) cannot interbreed then, according to evolution, is it possible that the two types of Beetles originated from the one original group?

And the answer is, "Yes, it is possible, and here's a plausible model for how it can happen." A model you can't even understand, let alone critique.


I'm not sure that I agree with you about needing more 'genetic information' since the hypothesis of evolution was once not dependant on genetic information. Smithers Bones has access to historical and genealogical information.

But you don't. You can't tell us anything about this "historical and genealogical information."

[ericmurphy]

And before you get all excited about my difference of opinion with sylas, Magellan, I will point out that at least he and I have some idea what we're talking about. It may turn out that sylas is factually correct and I am not. But that will not help you in the slightest in your arguments about speciation, since talking about the phylogenetic relationships, or differences and similarities, of organisms which diverged hundreds of millions of years ago has almost zero applicability to a discussion of a model of speciation. And you will still be wrong that there are more genetic differences between any two living humans and an ancestor from more than a million years ago, since the last common ancestor of all living humans lived less than 10% of that time in the past.

[sylas]

Because humans and chickens share a common ancestor that is more recent than the ancestor they share with a primitive amniote.

That's insufficient; and also I think untrue (depending on what you mean by primitive).

Assuming roughly constant rates of divergence by time, you would need a common ancestor that is at least TWICE as recent. And that ain't so. The lineage of chickens and humans has been separated for at least 220 million years, and certainly a lot more than 150 million years.

In the taxonomy of amniotes, chickens and humans are about as widely separated as you can get. That is, the most recent common ancestor of chickens and humans is also the most recent common ancestor of all extant amniotes; and this common ancestor probably lived of the order of 300 million years ago.



Why? They have a more recent common ancestor than either one does with a stem-group amniote. By your own reasoning (which is the same as mine) they are more closely related than either is to a stem-group amniote.

No, they don't. We need to get the basic information right before applying reasoning to get sensible conclusions.

I refer to Phylogeny and Classification of Amniotes (http://tolweb.org/articles/?article_id=462) at the "Tree of Life" web project. From that page:

Amniota is defined as "the most recent common ancestor of extant mammals and reptiles, and all its descendants" (Gauthier et al., 1988). It is divided into two stem-based taxa: Synapsida (mammals and their extinct relatives) and Sauropsida (reptiles and their fossil relatives). The autapomorphies of Amniota are listed in the "Characteristics" section of the Tree of Life page.

Chickens are within Sauropsida; humans within Synapsida.


I don't think so. But to know for sure, you'd have to know how much difference there is between the earliest amniotes (which is what I'm talking about, not, as Magellan apparently is, any old amniote which would of course include living mammals and birds) and the last common ancestor of synapsids and sauropsids. Given the murkiness of that part of the phylogenetic tree, I don't think any firm estimates can be made, although I think it's pretty safe to assume that there are a fair number of branching between the earliest amniotes and the LCA of synapsids and sauropsids.

I was using your "300 million years" qualifier, which would be a primitive amniote right around the most recent common ancestor of humans and chickens; which IS the LCA of synapsids and sauropsids.



But of course none of this is remotely relevant to a discussion of speciation. The differences between humans and chickens have been accumulating through the last several hundred million years and countless individual speciation events.

Of course. I am simply focusing in on a specific point where I think you are incorrect, and this can confuse the subsequent discussion.

In my experience, by the way, this is the real benefit of these discussions. Magellan is going to learn nothing; you and I are going to be able to sort this out and make progress in the background subjects being introduced into the thread.

Cheers -- sylas

[ericmurphy]

That's insufficient; and also I think untrue (depending on what you mean by primitive).

Could be. It depends on how much time there is between the most basal (which is what I mean by "primitive") amniotes and the divergence between synapsids and sauropsids. If that time is relatively short, I'll concede the point. My understanding of the fossil record of very early amniotes is that there is a great deal of uncertainty in the matter.


Assuming roughly constant rates of divergence by time, you would need a common ancestor that is at least TWICE as recent. And that ain't so. The lineage of chickens and humans has been separated for at least 220 million years, and certainly a lot more than 150 million years.

Probably not. Although the earliest amniotes are known to be at least 340 million years old, so we're in the ballpark. But I agree, you're probably right. Not that it helps Magellan's argument. His argument is much more general: that all living organisms are more different genetically than any ancestor, which is manifestly false. While humans and chickens might be more different genetically than the earliest amniotes, humans and other mammals are certainly not more different genetically than they are from the earliest amniotes.

I admit I went out on a limb with the chicken-human-amniote thing. :-)


In the taxonomy of amniotes, chickens and humans are about as widely separated as you can get. That is, the most recent common ancestor of chickens and humans is also the most recent common ancestor of all extant amniotes; and this common ancestor probably lived of the order of 300 million years ago.

It does seem like synapsids and sauropsids diverged very early in the history of Amniota. The Paleos (http://www.palaeos.com/) site has been down for a while, but last time I looked it showed Synapsida as the earliest branching from Amniota.




No, they don't. We need to get the basic information right before applying reasoning to get sensible conclusions.

But they could be. It depends on whether or not the smallest group enclosing both chickens and humans also encloses the earliest amniotes. If it doesn't, then humans and chickens are more closely related than either is to that early amniote, just as any two eutherians are more closely related to each other than either is to any mammal which is not a eutherian.


I refer to Phylogeny and Classification of Amniotes (http://tolweb.org/articles/?article_id=462) at the "Tree of Life" web project. From that page:

Amniota is defined as "the most recent common ancestor of extant mammals and reptiles, and all its descendants" (Gauthier et al., 1988). It is divided into two stem-based taxa: Synapsida (mammals and their extinct relatives) and Sauropsida (reptiles and their fossil relatives). The autapomorphies of Amniota are listed in the "Characteristics" section of the Tree of Life page.

If there are no groups intermediate between the LCA of synapsids and sauropsids, and the LCA of all amniotes, then you're definitely right. But just because that's how Amniota is currently defined doesn't mean it's actually true. We diagnose natural groups; we don't define them.


Chickens are within Sauropsida; humans within Synapsida.

Right. But are Sauropsids and Synapsids combined the same thing as Amniota? Probably. In which case you're definitely right. If not, you're only probably right. :-)


I was using your "300 million years" qualifier, which would be a primitive amniote right around the most recent common ancestor of humans and chickens; which IS the LCA of synapsids and sauropsids.

Agreed.


Of course. I am simply focusing in on a specific point where I think you are incorrect, and this can confuse the subsequent discussion.

I tend to agree with you that I'm probably incorrect. In my defense I'll point out that the very early history of Amniota is not very well known.


In my experience, by the way, this is the real benefit of these discussions. Magellan is going to learn nothing; you and I are going to be able to sort this out and make progress in the background subjects being introduced into the thread.

Absolutely. I'm glad it's not just Magellan and me in here. Such a conversation may as well be via e-mail, which I would have ended long ago.

But speaking of the whole amniote-sauropsid thing, here's a good paper on the possible monophyly of "Reptilia," (http://sysbio.oxfordjournals.org/content/53/5/815.full)

[magellan004]

Could be. It depends on how much time there is between the most basal (which is what I mean by "primitive") amniotes and the divergence between synapsids and sauropsids. If that time is relatively short, I'll concede the point. My understanding of the fossil record of very early amniotes is that there is a great deal of uncertainty in the matter.



Probably not. Although the earliest amniotes are known to be at least 340 million years old, so we're in the ballpark. But I agree, you're probably right. Not that it helps Magellan's argument. His argument is much more general: that all living organisms are more different genetically than any ancestor, which is manifestly false. While humans and chickens might be more different genetically than the earliest amniotes, humans and other mammals are certainly not more different genetically than they are from the earliest amniotes.

I admit I went out on a limb with the chicken-human-amniote thing. :-)



It does seem like synapsids and sauropsids diverged very early in the history of Amniota. The Paleos (http://www.palaeos.com/) site has been down for a while, but last time I looked it showed Synapsida as the earliest branching from Amniota.





But they could be. It depends on whether or not the smallest group enclosing both chickens and humans also encloses the earliest amniotes. If it doesn't, then humans and chickens are more closely related than either is to that early amniote, just as any two eutherians are more closely related to each other than either is to any mammal which is not a eutherian.



If there are no groups intermediate between the LCA of synapsids and sauropsids, and the LCA of all amniotes, then you're definitely right. But just because that's how Amniota is currently defined doesn't mean it's actually true. We diagnose natural groups; we don't define them.



Right. But are Sauropsids and Synapsids combined the same thing as Amniota? Probably. In which case you're definitely right. If not, you're only probably right. :-)



Agreed.



I tend to agree with you that I'm probably incorrect. In my defense I'll point out that the very early history of Amniota is not very well known.



Absolutely. I'm glad it's not just Magellan and me in here. Such a conversation may as well be via e-mail, which I would have ended long ago.

But speaking of the whole amniote-sauropsid thing, here's a good paper on the possible monophyly of "Reptilia," (http://sysbio.oxfordjournals.org/content/53/5/815.full)

What do you now conclude about the extent of differences between the Amniote Ancestor, Chickens and Humans?

Magellan?

[ericmurphy]

What do you now conclude about the extent of differences between the Amniote Ancestor, Chickens and Humans?

Magellan?

What do you now conclude about the common ancestor of amniotes, humans, and dogs, Magellan?

Your claim—that the differences between any two members of a group is greater that between either of them and a distant ancestor—is already toast. You can't even follow my discussion with sylas.

Just because you happened to get lucky with your guess, when you don't even know why you said what you said, does not help your pathetic attempts at addressing my model of speciation.

Nothing you can say about humans, chickens, and a basal amniote has the slightest bearing on your little problem there.

[sylas]

I think we are pretty much agreed now; current evidence suggests that the difference between humans and chickens is greater than the difference between either, and primitive amniotes 300 million years ago.

Not to belabor this; but there a couple more issues worth clearing up, IMO.

Unresolved matters with very early amniotes


My understanding of the fossil record of very early amniotes is that there is a great deal of uncertainty in the matter.

There is a lot of uncertainty in the placement of various now extinct groups within amniota. The phylogeny of living amniotes, however, is all but settled thanks to molecular techniques. The diagnosed phylogeny of living amniotes really does mean that humans and chickens will be more different from each other than either is from any of the early amniotes; and the issues with primitive amniotes don't have any impact on this conclusion.


Added in edit. I overstate the matter. I wrote the above while thinking of an improper definition of amniote. More below. Be that as it may, it's still the case that the various outstanding issues with primitive amniotes don't have any significant bearing upon the relative difference between human and chicken and basal amniotes.

Definition and diagnosis


But they could be. It depends on whether or not the smallest group enclosing both chickens and humans also encloses the earliest amniotes. If it doesn't, then humans and chickens are more closely related than either is to that early amniote, just as any two eutherians are more closely related to each other than either is to any mammal which is not a eutherian.

This is still not correct.

Evidence does indeed indicate that the LCA of humans and chickens is also the LCA of all the amniotes; but we don't need that, nor did I assume it last time. Even if there is a more recent LCA for chickens and humans, your conclusion still doesn't follow. For humans and chickens to be more closely related to each other than to the earliest (basal) amniotes, you would need the LCA of chickens and humans to be roughly half as ancient as the basal amniotes. I don't think that has ever been seriously considered. After all -- archaeopteryx is about 150 Mya. Any credible phylogeny has the LCA of humans and chickens well before that… and hence more distant from each other than from an ancestor living 300 Mya.

By the way, the definition of "Amniote" is the smallest natural group (clade) including all living mammals and living reptiles. Hence -- by definition -- there is no such thing as an early amniote which is earlier than the LCA of living amniotes. The LCA will have ancestors, of course, but they will not be amniotes in this definition. Paleontology may augment taxonomy with groups defined as the descendants of the LCA of some living group and another extinct group; but I don't think that has been done with Amniota. Larger natural groups are labeled with a different name.


Added in edit: oops. I was wrong.

Amniota is actually defined by a particular characteristic.

vertebrates that undergo embryonic or fetal development within an amnion.
The amnion is a fluid filled sac that forms around a foetus. This definition used used by Miriam-Webster, and many other sources. Given this style of definition, the LCA of living amniotes is not the basal amniote. The difference is probably of the order of 20 million years; not enough to materially alter my conclusions. But my underlying comment on the definition was incorrect and I am taking the chance to fix it.

Amniota is not defined as the descendants of the LCA of synapsida and sauropsida. That is the best available diagnosis, but the definition is now and always has been the descendants of the LCA of living mammals and living reptiles; for the most distantly related extant amniotes (corrected in edit). There are, of course, a range of other proposals that have been developed over the years for the natural phylogeny within Amniota (listed in the page I cited previously), and none have implied any change the definition of Amniota. I also do not think anyone has seriously proposed a phylogeny where Aves is within Synapsida; and given the age of Archaeopteryx I am confident that no credible phylogeny has ever carried the implication that humans and chickens are more closely related than either one to the basal amniotes.

Cheers -- sylas

PS. I endorse your comments to Magellan. This whole aside has no bearing on the models of speciation, and gives no support whatever to the many errors Magellan has been making. Magellan, you really do need to settle down and learn a lot more of the basics before you'll be particularly coherent with a more detailed discussion; even assuming you were serious about trying to give a coherent critique of conventional biology.

The differences between humans and any of our ancestral paleospecies are the result of the accumulation of many differences over many generations. This difference is more than enough to mean humans are a radically different species from ancestral populations sufficiently far in the past. The actual numbers don't matter all that much. But for what it is worth, I reckon 2 million years would be ample in the human lineage to mean ancestors from that far back, if somehow replicated into the present, would be a plainly different species to living humans. When you have two populations which have had no shared gene flow, for whatever reason, the cummulative difference should be plenty to give two distinct species over a million years or so. In practice, speciation will occur in less time than this; but rates of divergence can vary in different circumstances.

The model, however, is divergence by the accumulation of many differences generation by generation by generation, with no one identifiable generation or point of change where you pin down the speciation to a unique point in time.[/QUOTE]




If there are no groups intermediate between the LCA of synapsids and sauropsids, and the LCA of all amniotes, then you're definitely right. But just because that's how Amniota is currently defined doesn't mean it's actually true. We diagnose natural groups; we don't define them.


Amniota is not defined as the descendants of the LCA of synapsida and sauropsida. That is the best available diagnosis, but the definition is now and always has been the descendants of the LCA of living mammals and living reptiles. There are, of course, a range of other proposals that have been developed over the years for the natural phylogeny within Amniota (listed in the page I cited previously), and none have implied any change the definition of Amniota. I also do not think anyone has seriously proposed a phylogeny where Aves is within Synapsida; and given the age of Archaeopteryx I am confident that no credible phylogeny has ever carried the implication that humans and chickens are more closely related than either one to the basal amniotes.

Cheers -- sylas

PS. I endorse your comments to Magellan. This whole aside has no bearing on the models of speciation, and gives no support whatever to the many errors Magellan has been making. Magellan, you really do need to settle down and learn a lot more of the basics before you'll be particularly coherent with a more detailed discussion; even assuming you were serious about trying to give a coherent critique of conventional biology.

The differences between humans and any of our ancestral paleospecies are the result of the accumulation of many differences over many generations. This difference is more than enough to mean humans are a radically different species from ancestral populations sufficiently far in the past. The actual numbers don't matter all that much. But for what it is worth, I reckon 2 million years would be ample in the human lineage to mean ancestors from that far back, if somehow replicated into the present, would be a plainly different species to living humans. When you have two populations which have had no shared gene flow, for whatever reason, the cummulative difference should be plenty to give two distinct species over a million years or so. In practice, speciation will occur in less time than this; but rates of divergence can vary in different circumstances.

The model, however, is divergence by the accumulation of many differences generation by generation by generation, with no one identifiable generation or point of change where you pin down the speciation to a unique point in time.

[magellan004]

What do you now conclude about the common ancestor of amniotes, humans, and dogs, Magellan?

Your claim—that the differences between any two members of a group is greater that between either of them and a distant ancestor—is already toast. You can't even follow my discussion with sylas.

Just because you happened to get lucky with your guess, when you don't even know why you said what you said, does not help your pathetic attempts at addressing my model of speciation.

Nothing you can say about humans, chickens, and a basal amniote has the slightest bearing on your little problem there.

We've only scratched the surface of the problems with evolution. Stay tuned.

Magellan

[ericmurphy]

I think we are pretty much agreed now; current evidence suggests that the difference between humans and chickens is greater than the difference between either, and primitive amniotes 300 million years ago.

Yeah, it would take quite a few branchings between the first divergence of amniotes from earlier stegocephalians and the first divergence of sauropsids and synapsids.


Not to belabor this; but there a couple more issues worth clearing up, IMO.

Unresolved matters with very early amniotes



There is a lot of uncertainty in the placement of various now extinct groups within amniota. The phylogeny of living amniotes, however, is all but settled thanks to molecular techniques. The diagnosed phylogeny of living amniotes really does mean that humans and chickens will be more different from each other than either is from any of the early amniotes; and the issues with primitive amniotes don't have any impact on this conclusion.

Definition and diagnosis

Yeah, I can live with that. There's certainly not much confusion about the phylogeny of crown-group amniotes.

But—let me ask you this: if the first divergence of sauropsids and synapsids had occurred (let's pick a figure) 85 million years ago, would you still say humans and chickens have more differences than either do from a stem-group amniote from (say) 350 million years ago?

I have a point to make here, that I'm pretty sure you'll agree with.



This is still not correct.

Evidence does indeed indicate that the LCA of humans and chickens is also the LCA of all the amniotes; but we don't need that, nor did I assume it last time. Even if there is a more recent LCA for chickens and humans, your conclusion still doesn't follow. For humans and chickens to be more closely related to each other than to the earliest (basal) amniotes, you would need the LCA of chickens and humans to be roughly half as ancient as the basal amniotes. I don't think that has ever been seriously considered. After all -- archaeopteryx is about 150 Mya. Any credible phylogeny has the LCA of humans and chickens well before that… and hence more distant from each other than from an ancestor living 300 May.

Yes, that is indeed my point. And you're right. There's no plausible scenario where the split between sauropsids and synapsids is half as long ago as the divergence of amniotes from other tetrapods.


By the way, the definition of "Amniote" is the smallest natural group (clade) including all living mammals and living reptiles. Hence -- by definition -- there is no such thing as an early amniote which is earlier than the LCA of living amniotes.

Well, the LCA of all amniotes was definitely an amniote. But there could be, at least in principle, an LCA of all amniotes which is not also the LCA of sauropsids and synapsids—since there are many extinct taxa in both groups. But I agree that if there is a distinction, it's one of just a few million years at most.


The LCA will have ancestors, of course, but they will not be amniotes in this definition.
Right. Any ancestor of the LCA of all amniotes cannot be an amniote.


Paleontology may augment taxonomy with groups defined as the descendants of the LCA of some living group and another extinct group; but I don't think that has been done with Amniota. Larger natural groups are labeled with a different name.

I'll take your word on that. It looks like the smallest group that encloses Amniota is Reptilomorpha, with Diadectomorpha as the sister group.


Amniota is not defined as the descendants of the LCA of synapsida and sauropsida. That is the best available diagnosis, but the definition is now and always has been the descendants of the LCA of living mammals and living reptiles. There are, of course, a range of other proposals that have been developed over the years for the natural phylogeny within Amniota (listed in the page I cited previously), and none have implied any change the definition of Amniota. I also do not think anyone has seriously proposed a phylogeny where Aves is within Synapsida; and given the age of Archaeopteryx I am confident that no credible phylogeny has ever carried the implication that humans and chickens are more closely related than either one to the basal amniotes.

Okay—I give. :-) But not for the reason Magellan has proposed, which is that any two living organisms are more diverse genetically than any proposed ancestor, which is preposterous. Two cousins are not more distant genetically than either is from a basal synapsid, for example, or even from an early hominid.


Cheers -- sylas

PS. I endorse your comments to Magellan. This whole aside has no bearing on the models of speciation, and gives no support whatever to the many errors Magellan has been making. Magellan, you really do need to settle down and learn a lot more of the basics before you'll be particularly coherent with a more detailed discussion; even assuming you were serious about trying to give a coherent critique of conventional biology.

And, to be honest, I had serious doubts about my claims wrt humans, chickens, and basal amniotes. But hey—if you're not willing to be wrong now and then, you'll never learn anything.


The differences between humans and any of our ancestral paleospecies are the result of the accumulation of many differences over many generations. This difference is more than enough to mean humans are a radically different species from ancestral populations sufficiently far in the past. The actual numbers don't matter all that much. But for what it is worth, I reckon 2 million years would be ample in the human lineage to mean ancestors from that far back, if somehow replicated into the present, would be a plainly different species to living humans. When you have two populations which have had no shared gene flow, for whatever reason, the cummulative difference should be plenty to give two distinct species over a million years or so. In practice, speciation will occur in less time than this; but rates of divergence can vary in different circumstances.

Indeed, for many organisms (especially plants), speciation can happen on human timescales.

[sylas]

We've only scratched the surface of the problems with evolution. Stay tuned.

You haven't scratched the surface at all. You haven't even GOT to the surface; you're still floating away somewhere in stratosphere, ungrounded in any understanding of biology.

Before you can make any coherent comment of any kind on evolution, either for or against, you need to get a much better basic understanding of evolution. This means comprehending existing models used in evolution, whether you agree with them or not. Until you do this, you will continue -- as throughout this entire thread -- to merely provide an example of someone who doesn't understand the subject.

It's worse than that. The biggest problem is not that you don't understand evolution or biology; it that you appear to refuse to understand it, and introduce -- repeatedly -- your own personal presumptions and inventions, which are not used in evolution, and which conflict with basic biological observations in the present.

Understand. THEN critique.

Cheers -- sylas

[sylas]

But—let me ask you this: if the first divergence of sauropsids and synapsids had occurred (let's pick a figure) 85 million years ago, would you still say humans and chickens have more differences than either do from a stem-group amniote from (say) 350 million years ago?

The stem group in that case would be easily the outlier -- more different from either descendant than the descendants are from each other.

Your example given of dogs, humans, and basal amniotes works well in this case. Dogs and humans are more similar to each other than either is to the basal amniote from which they both descended.


Right. Any ancestor of the LCA of all amniotes cannot be an amniote.

I've had to correct myself on that point, if we mean the LCA of all extant amniotes. I gave a poor definition previously. The actual definition is based on a particular character -- the "amnion" or "egg-sac" for a developing foetus. The character based definition does imply a level of ambiguity at the time of basal amniotes, without any sharp binary division. It is a matter of empirical evidence and inference (diagnosis) that the amnion did appear to arise in one particular shared lineage, which subsequently diverged into all the many diverse species of amniotes living today and in the past.

Cheers -- sylas

[magellan004]

You haven't scratched the surface at all. You haven't even GOT to the surface; you're still floating away somewhere in stratosphere, ungrounded in any understanding of biology.

Before you can make any coherent comment of any kind on evolution, either for or against, you need to get a much better basic understanding of evolution. This means comprehending existing models used in evolution, whether you agree with them or not. Until you do this, you will continue -- as throughout this entire thread -- to merely provide an example of someone who doesn't understand the subject.

It's worse than that. The biggest problem is not that you don't understand evolution or biology; it that you appear to refuse to understand it, and introduce -- repeatedly -- your own personal presumptions and inventions, which are not used in evolution, and which conflict with basic biological observations in the present.

Understand. THEN critique.

Cheers -- sylas

You have no idea. You think you have. You are a regurgitator. A human photocopier.

I'm not knocking that. It obviously works for some. How to win friends and influence people - tell everyone you're an expert in evolution. It's just not my favourite approach to knowledge.

Magellan.

[sylas]

Actually, I don't try to tell people how much I know; I don't need to and don't think it's useful. I talk about the subject directly and specifically; without speaking about myself at all. Look at the recent exchange Eric and I had on relatedness. Others who are familiar with the subject matter don't have much problem figuring out roughly how much knowledge I or others bring to discussion. It's not a competition between people; it's a mutual exploration of a subject.

I'm not an expert and I don't claim to be. This isn't an expert level discussion. This is a very low level discussion, trying to explain bog simple concepts that you haven't yet learned even to regurgitate accurately, which makes your pretensions of going further into analysis and criticism merely comical.

No-one can hope to do anything sensible in the way of analysis or criticism until they have a level of comprehension. No-one can hope to have any comprehension until they can at least regurgitate accurately. And the truly demented can even keep on avoiding sensible regurgitation.

You don't have an approach to knowledge -- you have avoidance of knowledge; at a level which I am suspect is substantially deliberate trolling and game playing. My posts, by the way, are my own work; except where explicitly cited otherwise. Any errors in my posts are my own.

[magellan004]

He simply radiates desperation. He's given up even the pretense of actually addressing my model.

A few pages ago I asked about setting up a computer model that covered what we have been discussing-

Let's say we have a computer model of the development of a group - it's split into two , differences accumulate then, after a long time, the two groups are brought together again.

How might our computer program determine whether the two groups can or cannot interbreed?

Magellan

[magellan004]

This is a confusion -

1.
First, to repeat what I was ACTUALLY pointing out: the biological species definition is NOT simply based on the notion of "cannot interbreed".
2.
Here -- yet again -- is the definition of the biological species definition provided at the Evolution 101 website, ...The biological species concept defines a species as members of populations that actually or potentially interbreed in nature, ...
3.
The point is that the real biological species concept is given in terms of cohesive groups which DO NOT interbreed, rather than CAN NOT interbreed;

I have no idea which one of those contradictory thoughts you are running with.

Magellan

[magellan004]

Here -- yet again -- is the definition of the biological species definition provided at the Evolution 101 website ...
The biological species concept defines a species as members of populations that actually or potentially interbreed in nature,



All organisms can interbreed with some organisms and not with others, so that definition is pretty meaningless in itself.

I was the one saying that Species is meaningless. Stop borrowing my material.

I went along with your definition of Species , now you are jettisoning it.


Magellan

[magellan004]

And before you get all excited about my difference of opinion with sylas, Magellan, I will point out that at least he and I have some idea what we're talking about. It may turn out that sylas is factually correct and I am not.

That's the least of your concerns. neither of you are factually correct.

Magellan

[sylas]

This is a confusion

The key point which is being consistently emphasized in all those extracts is that the essence of the biological species definition is "do not interbreed in nature", NOT in terms of "cannot interbreed".


I have no idea which one of those contradictory thoughts you are running with.

Those extracts are all saying the same thing. And it is something others have pointed out in the thread long before I got here. See, for example, msg #297 by Tiggy.


Minor nit here. While the above definition holds true in most cases, it is not true in all. A more precise definition is: "Speciation" is the process whereby one group of individual organisms which can freely interbreed splits into two different groups of individuals between which mixing of genetic material no longer naturally occurs, either due to genetic incompatibility or due to other differences (behavioral, territorial, etc.) Lions and tigers are two species but they still can be interbred and produce viable offspring (i.e Ligers). It's just that in the wild, they don't.

- T

Speciation is NOT defined by whether or not it is possible for cross breeding to occur between individuals in the different populations (that is, in terms of fertility only). Biological species are defined by whether or not cross breeding does occur in nature, or would occur given the absence of geographical separation mechanisms.

Truly, your only solution here is actually to learn more biology. Do that, and the "confusion" goes away. It isn't that the posts are contradictory; it is that you lack the background (or the will?) to follow what they are ALL saying.

Note that posts in a website like this, from interested amateurs discussing various individual points, cannot really give you the education you need. A textbook, or a course, or several textbooks, would be the best way to start learning more about the subject, and clear up your particular confusions. A willingness to learn is also essential.

[ericmurphy]

The stem group in that case would be easily the outlier -- more different from either descendant than the descendants are from each other.

Your example given of dogs, humans, and basal amniotes works well in this case. Dogs and humans are more similar to each other than either is to the basal amniote from which they both descended.



I've had to correct myself on that point, if we mean the LCA of all extant amniotes. I gave a poor definition previously. The actual definition is based on a particular character -- the "amnion" or "egg-sac" for a developing foetus. The character based definition does imply a level of ambiguity at the time of basal amniotes, without any sharp binary division. It is a matter of empirical evidence and inference (diagnosis) that the amnion did appear to arise in one particular shared lineage, which subsequently diverged into all the many diverse species of amniotes living today and in the past.

Cheers -- sylas

Right. As I said earlier, we diagnose natural groups; we don't define them (although, as a practical matter, we often do define groups where we have imperfect information about long-extinct members). While in practice we can "define" Amniota as "the LCA of humans and chickens and all of its descendants," or as the Paleos site put it, "the LCA of St. Patrick and snakes and all of its descendants," we should be diagnosing the group based on shared characteristics, among which is of course the signature feature of the clade, the amnion.

[ericmurphy]

You have no idea. You think you have. You are a regurgitator. A human photocopier.

I'm not knocking that. It obviously works for some. How to win friends and influence people - tell everyone you're an expert in evolution. It's just not my favourite approach to knowledge.

Magellan.

Magellan, you don't even know why your statement about chickens, humans, and a long-extinct stem-group amniote was correct and mine was incorrect. Sylas and I both do know.

Sylas does have an idea. I do have an idea.

You don't. Your a human Insinkerator.

So when you're done with your temper tantrum, maybe you can get back to discussing my model of how speciation happens, and see if you can figure it out. As sylas says, "understand first; then critique."

[ericmurphy]

A few pages ago I asked about setting up a computer model that covered what we have been discussing-

Let's say we have a computer model of the development of a group - it's split into two , differences accumulate then, after a long time, the two groups are brought together again.

How might our computer program determine whether the two groups can or cannot interbreed?

Magellan

One way would be simply to hand-enter a figure, based on estimates of actual divergence preventing interfertility in the real world, for differences among descendants. Any two virtual organisms which exceed that figure would be unable to interbreed.

Another way would be to model actual physical structures, of a "tab A into slot B" nature, such that if either of the two organisms diverged too far from that particular configuration, they would be unable to interbreed. Both of these models would be reflective of what happens in the real world, which is what useful models do.

[ericmurphy]

This is a confusion -

1.
2.
3.

I have no idea which one of those contradictory thoughts you are running with.

It's certainly no surprise that you would have "no idea" what someone else (or even you yourself) are talking about, but the two definitions sylas mentioned are hardly "contradictory." One is simply more restrictive than the other. In one definition, two organisms are conspecific if they can interbreed. In the other, two organisms are conspecific if a) they can interbreed, and b) they actually do interbreed in nature.

In my model, populations A and B would be the same species until there was no mutual interferility under the first definition. Under the second definition, they would be separate species as soon as actual interbreeding ceased, regardless of whether or not interbreeding was still technically possible. To give a real-world example (which you have been provided countless times), under the first definition lions and tigers are the same species; under the second definition they are different species.

Apparently "contradictory" is another one of those words Magellan is none too clear on.

[ericmurphy]

I was the one saying that Species is meaningless. Stop borrowing my material.

You're still the only one saying it. No one else here is saying the term is meaningless. Your halfwitted attempt at a definition is meaningless.


I went along with your definition of Species , now you are jettisoning it.

Not surprising you'd think so, but no. I've been using the same meaning for the term from the beginning.

What Magellan can't seem to grasp is the concept of an "operational definition." In my model, the "operational definition" of the term "species" is "a group of organisms among which interbreeding is possible, even if it is not actually occurring."

And Magellan, if you object and insist that we use the more restrictive definition, then you'll find speciation happens as soon as there is reproductive isolation, regardless of whether further interbreeding is possible. Which will make your objection that speciation cannot happen even more wrong.

[ericmurphy]

That's the least of your concerns. neither of you are factually correct.

Right. We both took opposite views, but we're somehow both incorrect.

Maybe Magellan thinks humans and chickens are both more different from and more similar to each other than either is to a hypothetical stem-group amniote.

The truth is, Magellan, you not only haven't the vaguest notion what sylas and I were talking about; you don't even know what you are talking about.

[ericmurphy]

A willingness to learn is also essential.

And this, sad to say, is the missing critical ingredient.

It's a good thing my aim here isn't to educate or persuade Magellan. That truly would be a fool's errand.

[magellan004]

You're still the only one saying it. No one else here is saying the term is meaningless. Your halfwitted attempt at a definition is meaningless.



Not surprising you'd think so, but no. I've been using the same meaning for the term from the beginning.

What Magellan can't seem to grasp is the concept of an "operational definition." In my model, the "operational definition" of the term "species" is "a group of organisms among which interbreeding is possible, even if it is not actually occurring."

And Magellan, if you object and insist that we use the more restrictive definition, then you'll find speciation happens as soon as there is reproductive isolation, regardless of whether further interbreeding is possible. Which will make your objection that speciation cannot happen even more wrong.

Read the following -

As Sylas and others have pointed out several times - we can have different species that can interbreed. So using the label 'Species' is meaningless - unless - we agree that Species means one thing - a classification of animal that can interbreed but that cannot interbreed with other kinds types of animals.




All organisms can interbreed with some organisms and not with others, so that definition is pretty meaningless in itself.

Here -- yet again -- is the definition of the biological species definition provided at the Evolution 101 website, ...The biological species concept defines a species as members of populations that actually or potentially interbreed in nature, ...



All organisms can interbreed with some organisms and not with others, so that definition is pretty meaningless in itself.

In my model, the "operational definition" of the term "species" is "a group of organisms among which interbreeding is possible, even if it is not actually occurring."



All organisms can interbreed with some organisms and not with others, so that definition is pretty meaningless in itself.

Now please try to resurrect a definition that you wish to use in our discussion. If you conclude that your own definition is ‘pretty meaningless’ then we’ll have to say evolution is based on a meaningless concept.

It’s up to you. I’ll go along with whatever definition you pick (until you next undermine yourself).

Magellan

[magellan004]

One way would be simply to hand-enter a figure, based on estimates of actual divergence preventing interfertility in the real world, for differences among descendants. Any two virtual organisms which exceed that figure would be unable to interbreed.


I agree with that.
(And a brave answer, I must say.)

Such a test -
1. Has no time requirement,
2. Is not dependent on any numbers of individuals,
3. Is done on an individual by individual basis,
4. Has nothing to do with accumulated change. One change triggers it.

Your test is exactly what I was proposing - we look for the first individual with a certain difference that we can say causes lack of ability to interbreed.

And also note that according to your test , the first individual we find with this arbitrary difference becomes the first animal in the new species.

Remember Post 1107. We will be revisiting it often.

Magellan

[ericmurphy]

Read the following -

Now please try to resurrect a definition that you wish to use in our discussion.

Magellan, I just gave you the definition I'm using in discussions of my model. If you simply lack the intellectual horsepower to understand that extremely simple operational definition—"two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed"—then I'm afraid I can't help you.


If you conclude that your own definition is ‘pretty meaningless’ then we’ll have to say evolution is based on a meaningless concept.

I concluded that your definition—"a classification of animals that can interbreed"—is "pretty meaningless."

Do try to keep up.


It’s up to you. I’ll go along with whatever definition you pick (until you next undermine yourself).

You can't remember any definition I give you from one post to the next.

[ericmurphy]

I agree with that.
(And a brave answer, I must say.)

What's "brave" about it, Magellan? Given that I have some notion of how speciation actually happens, it's not too hard to figure out conceptually how it would be modeled computationally, even if I don't have the programming expertise to actually write the code to do it.


Such a test -
1. Has no time requirement,
2. Is not dependent on any numbers of individuals,
3. Is done on an individual by individual basis,
4. Has nothing to do with accumulated change. One change triggers it.

Nope. Wrong on every count. We can expect the number of mutations to accumulate with every generation. Given a threshold value for the number of mutations necessary to amount to speciation, of course the number of generations, and hence of time, is a "requirement."

If selection is modeled (and it should be, if the model is to have any resemblance to reality), then the number of individuals is important, because small numbers of individuals typically go extinct as deleterious mutations are much more likely to go to fixation in small populations. This has been explained to you repeatedly.

Of course such a simulation is done on an individual-by-individual basis. Mutations occur in individuals.

"One change" won't trigger it if there's a minimum number of mutations that results in mutual interfertility. A properly modeled simulation would show decreasing fertility with increasing numbers of mutations. As has been repeatedly pointed out to you, in real life, interfertility is not simply 100% or zero. The interfertility of any wild population is somewhere between 100% and zero.


Your test is exactly what I was proposing - we look for the first individual with a certain difference that we can say causes lack of ability to interbreed.

What "test" do you imagine you were proposing, Magellan? You don't have any tests, and you haven't "proposed" any tests. We already know what causes the lack of ability to interbreed. It's not like there's any mystery about it. In most cases, there are numerous causes, no one of which forms a bar to interbreeding but which taken together do form a bar to interbreeding. That's not even an issue, in the real world. The issue is, you don't believe it's possible to start out with one group of interbreeding individuals and end up with two groups of individuals, between which groups interbreeding is no longer possible.

Do you think you can remember that for more than one post?


And also note that according to your test , the first individual we find with this arbitrary difference becomes the first animal in the new species.

Why do you think this is important, Magellan? There are many individuals which can still interbreed after the first individual is born that cannot. You seem to have this notion that as soon as one individual cannot interbreed, every individual after that point cannot also interbreed.

It's like a comic-book version of speciation.


Remember Post 1107. We will be revisiting it often.

If you think post 1107 outlines an exhaustive list of all the events involved in the process of speciation, you are sadly mistaken. The only question I was answering was the only one you asked:


How might our computer program determine whether the two groups can or cannot interbreed?

it is not a list of all the mechanisms involved in speciation. So since the only question you asked was answered in post 1107, constant revisiting of it would be evidence of nothing more than your inability to remember one simple point.

[ericmurphy]

Magellan appears to have forgotten that I have already proposed a model under which speciation can happen. A computer simulation would probably include a modeling of all of these events and processes:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.

http://www.planet-deepblu.com/~eric/graphic_links/Isolation.png

Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.

http://www.planet-deepblu.com/~eric/graphic_links/InterfertilityVsDifferences.png

After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.

http://www.planet-deepblu.com/~eric/graphic_links/GeneticDriftV2.png

Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.

http://www.planet-deepblu.com/~eric/graphic_links/Interbreeding.png

As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.

[magellan004]

Magellan, I just gave you the definition I'm using in discussions of my model. If you simply lack the intellectual horsepower to understand that extremely simple operational definition—"two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed"—then I'm afraid I can't help you.

All organisms are capable of interbreeding. That's what you said. Therefore all organisms belong to one species. Where does the 'two' come from?

Perhaps you mean -
Species - 'two populations of organisms which belong to the same species if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed.'

That's remedial.

Perhaps you mean- ' organisms which are actually capable of interbreeding, regardless of whether or not they actually do interbreed.'

According to you that's meaningless.

Perhaps you mean- ' two populations of organisms which are actually capable of interbreeding, regardless of whether or not they actually do interbreed.'

More meaningless than ever.

How about you try again ? -
Species : ...

And don't blame me - you said this stuff about definitions which involve interbreeding was meaningless. It's your mess.

Magellan

[ericmurphy]

All organisms are capable of interbreeding.
Well, except for the enormous number of asexually-reproducing species, to which the term "interbreeding" doesn't even apply (unless you think LGT amounts to "interbreeding").

Even when you're mischaracterizing other people's statements, you still can't help getting most of it wrong.


That's what you said. Therefore all organisms belong to one species. Where does the 'two' come from?

You're once again mistaking your own bad, wrong, broken definition of a term for my definition. I gave you my definition. You quoted my definition. Why do you keep confusing it with your own misdefinition, Magellan?


Perhaps you mean -
Species - 'two populations of organisms which belong to the same species if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed.'

Or, maybe I just mean what I actually said: "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed"


That's remedial.

No, it's English. If you can't understand English, there's nothing I can do about that.


Perhaps you mean- ' organisms which are actually capable of interbreeding, regardless of whether or not they actually do interbreed.'

Or perhaps I mean what I actually said: "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed."


According to you that's meaningless.

No. I wasn't talking about my definition. I was talking about your definition, "a classification of organisms which can interbreed." That is "pretty much meaningless."

You do understand that you and I are two different people, right? And that statements you make are your statements, and statements I make are my statements? And that you can't just make statements and then attribute them to me? That you can't say that because I say one of your statements is meaningless, that means I'm saying my own statements are meaningless?

Do you EVER tire of taking your own bad, wrong, broken definitions and then pretend they're actually your opponents' definitions? Really, Magellan; you need a new schtick.

Do we need to get these sorts of issues straightened out, still?


Perhaps you mean- ' two populations of organisms which are actually capable of interbreeding, regardless of whether or not they actually do interbreed.'

Maybe I mean, "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed"


More meaningless than ever.

How about you try again ? -
Species : ...

And don't blame me - you said this stuff about definitions which involve interbreeding was meaningless. It's your mess.

I don't have a "mess," Magellan. You do. It's that tangled mass of dysfunctional nerve cells you use for a brain.

I'm using one, and only one, operational definition of the term "species" in my model: "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed."

[magellan004]

What's "brave" about it, Magellan? Given that I have some notion of how speciation actually happens, it's not too hard to figure out conceptually how it would be modeled computationally, even if I don't have the programming expertise to actually write the code to do it.



Nope. Wrong on every count. We can expect the number of mutations to accumulate with every generation. Given a threshold value for the number of mutations necessary to amount to speciation, of course the number of generations, and hence of time, is a "requirement."

If selection is modeled (and it should be, if the model is to have any resemblance to reality), then the number of individuals is important, because small numbers of individuals typically go extinct as deleterious mutations are much more likely to go to fixation in small populations. This has been explained to you repeatedly.

Of course such a simulation is done on an individual-by-individual basis. Mutations occur in individuals.

"One change" won't trigger it if there's a minimum number of mutations that results in mutual interfertility. A properly modeled simulation would show decreasing fertility with increasing numbers of mutations. As has been repeatedly pointed out to you, in real life, interfertility is not simply 100% or zero. The interfertility of any wild population is somewhere between 100% and zero.



What "test" do you imagine you were proposing, Magellan? You don't have any tests, and you haven't "proposed" any tests. We already know what causes the lack of ability to interbreed. It's not like there's any mystery about it. In most cases, there are numerous causes, no one of which forms a bar to interbreeding but which taken together do form a bar to interbreeding. That's not even an issue, in the real world. The issue is, you don't believe it's possible to start out with one group of interbreeding individuals and end up with two groups of individuals, between which groups interbreeding is no longer possible.

Do you think you can remember that for more than one post?



Why do you think this is important, Magellan? There are many individuals which can still interbreed after the first individual is born that cannot. You seem to have this notion that as soon as one individual cannot interbreed, every individual after that point cannot also interbreed.

It's like a comic-book version of speciation.



If you think post 1107 outlines an exhaustive list of all the events involved in the process of speciation, you are sadly mistaken. The only question I was answering was the only one you asked:



it is not a list of all the mechanisms involved in speciation. So since the only question you asked was answered in post 1107, constant revisiting of it would be evidence of nothing more than your inability to remember one simple point.

That was a quick retraction.
Post 1107:

How might our computer program determine whether the two groups can or cannot interbreed?

One way would be simply to hand-enter a figure ... for differences among descendants. Any two virtual organisms which exceed that figure would be unable to interbreed.

The computer uses one and only one piece of data to decide whether Group A and Group B can interbreed - an inputted figure. Compare one organism with another using that difference figure.

There is no calculation that the computer makes that includes time or numbers.
The calculation is (according to you) -
1. Subtract Organism 2'a differences figure from Organism 1's differences figure.
2. If result > x then the two organisms cannot interbreed.
That test could be done with generation two with only two organisms left.

If you now want to revise your test to include mutations and time and numbers of individuals then please do so.

Until then your test is exactly the same as my test - 'Is this individual different to its parents enough for us to say that the individual cannot interbreed with animals that it's parents can interbreed with?'

Nothing to do with accumulated differences. It happens in one generation.


Magellan

[ericmurphy]

For seventy-five pages now, Magellan has been moaning and whining and mumbling about how he can't figure out what the words we're using even mean, despite the fact that all of the terms in use have been defined exhaustively.

[ericmurphy]

That was a quick retraction.

A quick retraction of what, Magellan?


Post 1107:

Which answers a single question:


How might our computer program determine whether the two groups can or cannot interbreed?

It's not an answer to the question you didn't ask but are now pretending you did ask, which is "How would a computer simulation model the entire process of speciation?"

If you'd asked that question, you would have gotten an answer similar to post #1116.


The computer uses one and only one piece of data to decide whether Group A and Group B can interbreed - an inputted figure. Compare one organism with another using that difference figure.

That decision is for one thing and one thing only: can these two organisms interbreed? That is NOT a modeling of how it came to be that two organisms cannot interbreed.


There is no calculation that the computer makes that includes time or numbers.
There is in a calculation that the computer makes to determine how long it takes to achieve speciation. Is that what's being modeled here? It is, isn't it? From your post #1100:


Let's say we have a computer model of the development of a group - it's split into two , differences accumulate then, after a long time, the two groups are brought together again.

That is what the model is simulating: how we end up with two different species after starting out with one species. NOT how to determine whether or not two organisms can interbreed.


The calculation is (according to you) -
1. Subtract Organism 2'a differences figure from Organism 1's differences figure.
2. If result > x then the two organisms cannot interbreed.
That test could be done with generation two with only two organisms left.

That would not be a model of speciation. That would be a single calculation within a larger simulation.

Even the simplest concepts seem to be beyond you, Magellan.


If you now want to revise your test to include mutations and time and numbers of individuals then please do so.

I'm not talking about a "test," a test you claim you have but do not. My model is of speciation. Any model of speciation must take time (or at least number of generations) into account. Simply determining whether or not two organisms can interbreed does not need to consider time, or even generations. The two organisms in question can even be of the same generation, or of different generations (so long as they're both still alive, not something I would normally assume would need to be specified, but in your case…)


Until then your test is exactly the same as my test - 'Is this individual different to its parents enough for us to say that the individual cannot interbreed with animals that it's parents can interbreed with?'

Nothing to do with accumulated differences. It happens in one generation.

WHAT happens in one generation, Magellan?

[ericmurphy]

The question Magellan is proposing—how do we test whether or not two organisms can interbreed—is mind-numblingly stupid.

How do we test that, Magellan? We try to get them to interbreed. If they can't, then they can't.

It's like you're asking how do we test whether a stone will fall if we drop it.

We drop it.

If it falls, then it falls.

Also, one of the biggest problems you have, Magellan, is that you simply have no idea what you're talking about. This simple fact means you have difficulty asking clear, coherent questions that aren't laden with ambiguity. It's bad enough that much of the time you are deliberately ambiguous. But what makes matters worse is that you are way, way, WAY over your head in trying to discuss any subject in biology in particular and science in general, since you seem to have no education at all in the sciences. I'm certainly no scientist myself, and have no formal education in any scientific discipline beyond high school, but at least I've read a bit in the area and have some notion of general principles. I can at least speak coherently about subjects like common descent, inheritance, speciation, and how natural groups are diagnosed by the possession of shared characteristics.

You can't do any of these things, and worse, you don't want to be able to do any of these things. Your own native anti-intellectualism and fear and hatred of science means you'll never learn how to do any of these things. Your quixotic attempt to prove all of science wrong is hampered by the fact that you don't know what science claims in the first place.

[magellan004]

For seventy-five pages now, Magellan has been moaning and whining and mumbling about how he can't figure out what the words we're using even mean, despite the fact that all of the terms in use have been defined exhaustively.

Why don't you tell us what Species means?
Defining Species as 'two organisms belong to the same species' is begging the question . What do they belong to?

'A circle is anything with shape of a circle' < --- Begging the question. This is a concept that eludes you.

'Country - two people belong to the same country if they both fly the same flag.' < --- begging the question. Does not tell us what a country is. Only tells us about two people.

Species - two organisms belong to the same species if ... < -- Does not tell us what Species is, the thing they belong to.

Now try again. Don't use the word you are defining in the definition; otherwise you will be begging the question.

Species - a species is ...

(This is basic reasoning. It's not that hard.)

Magellan

[magellan004]

That decision is for one thing and one thing only: can these two organisms interbreed? That is NOT a modeling of how it came to be that two organisms cannot interbreed.

What in heaven's name are you talking about?

You gave a test for determining whether Group A could interbreed with Group B.
To do that you test each individual.
'Is this individual different to others by Factor X?'

That can only mean (and I certainly hope what you meant was ) 'If all individuals in Group B have Factor X difference to Group A individuals then Group B and Group A are separate species.'

Of course that means that Group B individuals cannot breed with Group A individuals. What else could it mean????

That must mean that it came to be that one organism could not interbreed with another organism because that organisms was born with Factor X difference.

What else could it possibly mean?

If that is not how your test works then please tell me.

Magellan

[ericmurphy]

Why don't you tell us what Species means?

You've repeatedly quoted my definition in this very thread, Magellan, which is proof positive that you already know I've told you what it means. It would be one thing if you'd asked for clarification of the definition I gave you. Instead, you keep pretending I never gave it to you in the first place.


Defining Species as 'two organisms belong to the same species' is begging the question . What do they belong to?

Since neither I nor anyone else has ever defined "species" this way, one wonders what you think you're accomplishing by claiming otherwise.


'A circle is anything with shape of a circle' < --- Begging the question. This is a concept that eludes you.

Find any quote from anyone in this or any thread which defines a "species" as meaning "all those organisms which belong to the same species."

Everyone who wants to can read this thread, Magellan. You can't get away with pretending people have said things they've never said, or not said things they demonstrable did say.


Now try again. Don't use the word you are defining in the definition; otherwise you will be begging the question.

I'll do that as soon as you find an instance where I have ever defined the word "species" in terms of the word "species."


(This is basic reasoning. It's not that hard.)

It seems to be pretty hard for you. I can't tell if you really do think anyone here has said "two organisms are the same species if they belong to the same species," in which case you're delusional, or if you know no one ever has, in which case you're lying. And frankly the distinction is unimportant.

[ericmurphy]

What in heaven's name are you talking about?

Why is it completely unsurprising that you would have no idea what I'm talking about?


You gave a test for determining whether Group A could interbreed with Group B.
To do that you test each individual.
'Is this individual different to others by Factor X?'

You test for whether or not two organisms can interbreed by seeing if they can interbreed. How hard is that?



That can only mean (and I certainly hope what you meant was ) 'If all individuals in Group B have Factor X difference to Group A individuals then Group B and Group A are separate species.'

No. It means if two organisms cannot mate and produce viable offspring then they are not the same species (absent special situations like one or both of them being sterile, one of them being dead, the sort of thing that normally would not need to be pointed out but which in your case do need to be pointed out).

We're supposed to be discussing how speciation happens, but Magellan is still mystified by how we might find out if two organisms can interbreed. At this rate, this discussion could go for centuries. Which is fine with me. The dumber Magellan looks, the happier I am.


Of course that means that Group B individuals cannot breed with Group A individuals. What else could it mean????

Well, I don't know, Magellan. You're the one who seems to be having trouble with figuring out how we could tell if two organisms can interbreed or not.


That must mean that it came to be that one organism could not interbreed with another organism because that organisms was born with Factor X difference.

Or, factors A, B, C, D, E, F, G, H, I, J, K, L, M, etc. differences.


What else could it possibly mean?

If that is not how your test works then please tell me.

We test if two organisms are interfertile by seeing if they can mate and produce viable offspring.

How do you tell if a rock will fall if you drop it, Magellan?

At some point, you have to assume Magellan is trying to make fun of me by pretending to be really, really stupid and getting me to answer really, really stupid questions. But he doesn't seem to realize what that makes him look like.

But maybe you're even more clueless than that. You were asking me about a computer simulation of the process of speciation. Magellan appears to think that such a model would have to try to figure out whether two virtual organisms could interbreed or not. No rational simulation would do any such thing. The model would be constructed so that a lack of interfertility is defined to result from a certain number of genetic differences. Such a lack of fertility would be an assumption of the program, and the model would be compared against observation to see if such an assumption would lead to phenomena such as are observed in the real world.

If, on the other hand, one wanted to model the process of loss of interfertility, rather than the process of speciation, that would be a matter of empirical investigation into what causes a lack of interfertility in the real world. Magellan seems unable to understand that such an investigation is distinct from an investigation into speciation. Any model of speciation assumes what is obvious from observation: organisms which differ genetically to a sufficient degree are generally unable to interbreed. We note that while organisms within the same genus are sometimes able to interbreed, we never see such interbreeding happen between members of different orders or classes. No bird will ever successfully interbreed with any mammal, nor will any squamate interbreed with any amphibian.

Again, Magellan is tripped up by his inability to comprehend straightforward biological concepts, and his inability to make fine distinctions between concepts like speciation and interfertility, which while are related are definitely not the same thing.

[ericmurphy]

Now, of course, Magellan will make a big deal out of any "assumption" that genetic differences can lead to a lack of interfertility. He will overlook the fact that that's not an "assumption" but rather an observation. We can and do easily observe that organisms which can interbreed are very similar genetically (within fractions of a percent of identity), whereas organisms which cannot interbreed have clearly observable genetic differences. Just because there are examples where the extent of the differences is close to the point where complete inability to interbreed results in ambiguous levels of interfertility does not change this fact. And, of course, that's a prediction of the model. If interfertility declines with increasing numbers of differences, we should expect that there is a point on that curve where interfertility becomes ambiguous. Whereas if Magellan were correct, and interfertility is always and everywhere either 100% or zero, that should never be the case. Every mating should either result in viable offspring or none at all, and all litters (for organisms which produce multiple offspring at once) should be exactly the same size.

[magellan004]

I'll do that (Define species) as soon as you find an instance where I have ever defined the word "species" in terms of the word "species."

You did it here-
Post 1114.
Species: "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed"

Now please give a definition of Species which does not include species in the definition.

Magellan

[ericmurphy]

You did it here-
Post 1114.
Species: "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed"

Now please give a definition of Species which does not include species in the definition.

Magellan

Nope. Sorry, Magellan. You'd be right if I said, "two populations of organisms are conspecific if they belong to the same species," but I didn't say that, did I? You'd also be right if I said, "two populations of organisms belong to the same species if they belong to the same species," but I didn't say that either, did I?

I said, "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed."

Which is equivalent to saying "two populations of organisms belong to the same species if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed."

So no, Magellan, that's not an instance of where I defined "species" in terms of the word "species."

Try again. Because I'm not going to give you the definition again until you find an instance where I defined "species" in terms of the word "species." (Even though I actually did give it again, but you probably didn't notice.)

Or—maybe you think I'm not allowed to use the word "species" in the sentence in which I define "species." That would be typical of you; some sort of lit-crit objection rather than a substantive one.

Let's try this:

"Species, n:
















a population of organisms which are capable of interbreeding even if they do not actually, due to e.g., geographic isolation, interbreed."

Is that enough of a cordon sanitaire between the word "species" and its definition? Or do I need a few more hard returns?

[sylas]

You did it here-
Post 1114.
Species: "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed"

Now please give a definition of Species which does not include species in the definition.

BOGGLE. I'm taking a permanent note of this post as the simplest and plainest demonstration that Magellan's "confusion" is deliberate.

He's playing dishonest and silly games; deliberately trying to sow distractions and confusions and derail any serious or sincere attempt to explain the things he keeps distorting.

The problem is that we keep commenting on these posts where Magellan is blowing smoke and trying to derail serious engagement with the topic -- and this derails the topic further from substantive biology. I'm doing it right now. That, I think, is the essence of Lao Tzu's objections earlier in the thread about "enabling" Magellan; it means that the thread as a whole is not at all useful for explaining anything.

And yet... I personally have a genuine and long standing interest (sometimes a horrified fascination) in how people avoid following even bog simple biological concepts in their efforts to descry evolutionary biology. I think others do also; there are a number of people following the thread after all.

I'll be adding another exclusively biology focused post soon. For the few who do find this long running train wreck to be interesting, it's still good for us to reflect on how to explain various concepts, and what details we may be simplifying along the way. Critical commentary from anyone seriously thinking about speciation will be welcome as always.


* * * * *

And as an encouragement. There really are people who come from a creationist style background who follow discussions on a board like this and get a bit of a help along the way to a better understanding of the natural world.

I recently had an email out of the blue from a creationist that I had been engaging here at TheologyWeb many years ago. She's since come around completely; having kept her interests in life and biology and gone on to learn and study it in detail; to the point of being about to start her PhD in neurobiology.

She didn't learn all that here, of course. She's long since gone well beyond my level of knowledge. But she still took the time to drop me an email with thanks for some posts made years ago, and to let me know what she's being doing since.

Cheers -- sylas

[magellan004]

I'll reply to Post 1126 as soon as I can but I just want to eliminate one extremely annoying habit of yours -

Or, factors A, B, C, D, E, F, G, H, I, J, K, L, M, etc. differences.


Do you understand how incredibly dumb that thinking is?


Take your 'Factor A'.
1. 'Does this individual differ from that individual by A?
Yes - Result = The two individuals cannot breed.
No - Result = The two individuals can breed.
We don't need Factor B. Factor B is irrelevant. So is Factor C and Factor D and Factor E. You are talking crap.

If you mean -
1. 'Does this individual differ from that individual by A?
Yes - Result = We have to test for Factor B.
No - Result = We have to test for Factor B.
Then why bother testing for Factor A?
Factor A is irrelevant.
You are talking crap.

That level of imbecility is very difficult even for a person with the patience of an Indonesian to cope with.

From now on we will refer to the difference that matters, the difference we test for - as Factor X.

Magellan

[ericmurphy]

And yet... I personally have a genuine and long standing interest (sometimes a horrified fascination) in how people avoid following even bog simple biological concepts in their efforts to descry evolutionary biology. I think others do also; there are a number of people following the thread after all.

That's my fascination, as well. I'm not persuaded it's an entirely healthy fascination, but so far it doesn't seem to have done me a great deal of harm.

[ericmurphy]

I'll reply to Post 1126 as soon as I can but I just want to eliminate one extremely annoying habit of yours -


Do you understand how incredibly dumb that thinking is?

Nope, because it's NOT dumb. You still have this entirely wrong idea that it is always and invariably a single factor that results in a complete loss of interfertility. If that were the case, we would not expect to see any instances, ever, of anything other than perfect interfertility or zero interfertility.

But we do see such instances. We see instances where mating produces offspring, but not viable offspring. We see matings where the results are sterile. We see results where simply the litter sizes are smaller. We see results where it simply takes many more mating attempts to produce offspring.

What's really incredibly dumb is not to be able to figure out the implications of those observations.


Take your 'Factor A'.
1. 'Does this individual differ from that individual by A?
Yes - Result = The two individuals cannot breed.
No - Result = The two individuals can breed.
We don't need Factor B. Factor B is irrelevant. So is Factor C and Factor D and Factor E. You are talking crap.

Take my factors A through Z.


Individuals with none of those factors have very high interfertility, approaching 100%
Individuals with five of those factors have slightly reduced fertility, where the number of offspring is reduced by 60%.
Individuals with 12 of those factors only occasionally produce any offspring at all.
Individuals with 18 of those factors very occasionally produce offspring, but those offspring are invariably infertile.
Individuals with all 26 of those factor never produce any offspring at all.


http://www.planet-deepblu.com/~eric/graphic_links/InterfertilityVsDifferences.png

And that doesn't even get into all the complications and additional results when we start talking about which specific factors are present. It may be that having factors A and J has a much greater detrimental effect on interfertility than factors, B, C, D, E, F, G, H, and I combined.

More of the Magellan problem in action:

http://www.planet-deepblu.com/~eric/graphic_links/GrayVsBandW.png


If you mean -
1. 'Does this individual differ from that individual by A?
Yes - Result = We have to test for Factor B.
No - Result = We have to test for Factor B.
Then why bother testing for Factor A?
Stop trying to guess what I mean, and read what I say.



Factor A is irrelevant.
You are talking crap.

Your thinking is crap.


From now on we will refer to the difference that matters, the difference we test for - as Factor X.

From now on we will continue to do what we have been doing for the entirety of this thread: explore the limits of how stupid Magellan is willing to appear to be in order to keep up the pretense that evolutionary theory makes no sense.

[ericmurphy]

When you give me a reason why it's impossible that an increase in genetic differences can cause a reduction, rather than an elimination, of interfertility, Magellan, then you'll have something.

Because so far, you ain't got nothin.'

[sylas]

Take your 'Factor A'.
1. 'Does this individual differ from that individual by A?
Yes - Result = The two individuals cannot breed.
No - Result = The two individuals can breed.
We don't need Factor B. Factor B is irrelevant. So is Factor C and Factor D and Factor E. You are talking crap.


Suppose you need two things for fertility. Say... the capacity for the sperm and egg to fertilize AND the capacity for the zygote to implant.

Suppose individuals are all either type "A" or type "a"; two forms of a fertilization factor. Couples that are both type "A", or both type "a", can fertilize, but "A" and "a" cannot.

Suppose also individuals are all either type "B" or type "b"; two forms of an implantation factor. Couples that are both type "B", or both type "b", will implant, but "B" and "b" cannot.

This simple description involves two factors, both of which are in two forms.

It's not enough to test for the fertilization factor, or the implantation factor, in isolation. You must test for both.

Real biology is a lot more complex than this of course; and all the additional complexity means that you have a lot more than only two factors involved.


From now on we will refer to the difference that matters, the difference we test for - as Factor X.


You're wrong, and the people speaking of Factors (plural) are correct. This is basic biology. Your personal insistence in declaring the more accurate descriptions as "imbecilic", and declaring what "WE" will use in future discussions is pointless.

The people who are trying to explain biology will continue to use the more biologically accurate notions, no matter what you think of them.

Eric is correct about how you test for fertility. You DON'T look for a particular factor. You simply mate them and see if you can get viable offspring.

Those interested in WHY couples might be infertile then go on to look for causes of infertility (the factors). Fertility is going to require (at least!)

Joining of the sperm and egg.
Implantation of the zygote.
Coherent development of the growing embryo
Maintenance of the embryo in until birth
Birth of a child able to survive to adulthood.
An eventual adult who is not sterile.
And so on and on and on...


All of these, in turn, require the interaction and maintenance of many different factors. Sufficient disruption of any one of these may lead to infertility.

There is no one "factor X" for determining fertility. Unless, of course, you simply define "factor X" to be fertility itself. Which is pretty pointless.

As a further point which bugs me in all these discussions; none of the above factors are simple binary decisions either. Sure -- for any particular mating event you either get implantation or not. But that doesn't mean the same couple always have implantation occur, or else never have implantation occur. These things always fall along a spectrum.

Hence, even Eric's test is insufficient as a one shot experiment. You can't conclude that a couple is infertile because of an unsuccessful mating. They might succeed on a second try. Or a third.

You know this from looking at fertility clinics for couple who have problems having a child. Some couples seem able to have children whenever they have sex. Others have to try, and try, and try again. There are sad cases of women who have repeated miscarriages... but then the joy when finally they succeed in a successful pregnancy!

This may be the same couple involved throughout. They may have a fertility problem of some kind, low sperm count, pregnancy problems, whatever. These are typically stochastic. There's a certain chance of successful mating. And that chance might be anything from 0 (totally infertile) to quite high (easily able to have children with no difficulty).

The same thing occurs across different populations. Some groups have a lot of trouble raising viable hybrids between the two groups. Others have only slightly reduced fertility.

Also, if you go to a fertility clinic, there IS no simple test for a single factor that will tell whether or not you are fertile. There is a whole BATTERY of tests which can take you a little bit along the way of identifying whether or not you might be fertile.

Your account is out of touch with elementary biology. Your declaration by fiat that you will continue to use the incorrect notions is an example of blind refusal to learn anything. As Eric notes, THIS is the biggest issue.

Your explicit and deliberate refusal to use the actual explanations given by the people who are describing the models you purport to critique dooms you to be forever attacking a strawman of your own invention.

Cheers -- sylas

[magellan004]

Take my factors A through Z.


Individuals with none of those factors have very high interfertility, approaching 100%
Individuals with five of those factors have slightly reduced fertility, where the number of offspring is reduced by 60%.
Individuals with 12 of those factors only occasionally produce any offspring at all.
Individuals with 18 of those factors very occasionally produce offspring, but those offspring are invariably infertile.
Individuals with all 26 of those factor never produce any offspring at all.



So your test , that you would program into the computer model is -
'If Individual 1 differs from Individual 2 by A and B and C and D ... and Z Then Individual 2 cannot breed with Individual 2.'

Now, I suggest that to save typing, we call ( A difference of A + B + C ... + Z) = Factor X.

Any problem with that?

If Individual 1 has Factor X and Individual 2 does not have Factor X then Individual 1 cannot breed with Individual 2.

If you don't like that then you type out -
A + B + C + D + E + F + G + H + I + J + K + L + M + N + O + P + Q + R + S + T + U + ZV + W + X + Y + Z in its entirety each time we talk about your test. OK?

A happy compromise.

Magellan

[ericmurphy]

Hence, even Eric's test is insufficient as a one shot experiment. You can't conclude that a couple is infertile because of an unsuccessful mating. They might succeed on a second try. Or a third.

Yes. If we wanted to find out if, e.g., two varieties of zebrafish from a South American stream were the same or different species, we'd probably take forty or so of each variety, and separate them into pairs (one of each variety), and see what happened. If we shuffled the pairs around, and still didn't get any offspring (taking into account things like breeding seasons, sufficient nutrients, etc.), we'd be reasonably confident they were two different species.

But it could well be that there could be reduced but still present interfertility. So we'd have to count the number of offspring, their fertility, etc.

The notion that fertility is an all-or-nothing deal is so awe-inspiringly vacuous it's really hard to believe Magellan's not just yanking our chain in pretending to think otherwise.

[magellan004]

When you give me a reason why it's impossible that an increase in genetic differences can cause a reduction, rather than an elimination, of interfertility, Magellan, then you'll have something.

Because so far, you ain't got nothin.'

I understand where you're coming from. You want to stick to your 'possibles' and probabilities. The last thing you want is to be nailed down to a testable concept.

You see 'potential to interbreed ' the wame way anyone else would see a locomotive heading their way when they are stuck on the tracks trying to pretend that it's all about vague notions.

The time is fast appraoching where you will have to agree that 'potential to interbreed' is an untestable, and therefore unscientific , concept. And that means only one thing - evolution is an unscientific fantasy.

Magellan

[ericmurphy]

So your test , that you would program into the computer model is -
'If Individual 1 differs from Individual 2 by A and B and C and D ... and Z Then Individual 2 cannot breed with Individual 2.'

Now, I suggest that to save typing, we call ( A difference of A + B + C ... + Z) = Factor X.

Any problem with that?

If Individual 1 has Factor X and Individual 2 does not have Factor X then Individual 1 cannot breed with Individual 2.

If you don't like that then you type out -
A + B + C + D + E + F + G + H + I + J + K + L + M + N + O + P + Q + R + S + T + U + ZV + W + X + Y + Z in its entirety each time we talk about your test. OK?

A happy compromise.

No. You're still assuming fertility is either 100% or zero. You're never going to get us to agree with that, so stop trying. You're simply factually wrong, and no amount of arguing about it is going to make you right.

In the meantime, Magellan, maybe you need to think a little bit more about what you're actually trying to model here. Are you trying to model how speciation might happen? Or are you trying to model how interfertility changes with increasing genetic differences (and you're not even doing that, because you're assuming a single genetic change results in fertility going from a sure thing to impossible, which is simply flat-out stupid)?

Because they're not the same thing.

If you're trying to model speciation, then it's going to be an assumption of your model that increasing differences result in decreased (but not suddenly zero) interfertility. Why? Because that assumption maps pretty well to actual observation, where increased genetic distance results in decreased (but not suddenly zero) interfertility.

I don't know why you'd have to model modes of fertility loss, since you can investigate that simply by observing living organisms. We can analyze genetic differences in real organisms, observe any loss or reduction in interfertility, and from that directly determine the relationship between the two. It's not clear why anyone would bother modeling such a phenomenon on a computer. It would be like "modeling" the rising and setting of the sun, which can be observed directly.

So which is it, Magellan? Do you want a model of speciation? Or do you want to model the interfertility effects of differing genetic distance?

Once you've decided on that, then you can actually have something resembling a rational discussion. Right now, you're just flopping about like a beached halibut.

[ericmurphy]

I understand where you're coming from.
No you don't. You've made it very plain you understand very little.


You want to stick to your 'possibles' and probabilities. The last thing you want is to be nailed down to a testable concept.

They're not "possibilities," or "probabilities." They're observational reality.

But what are you trying to test, Magellan? Are you trying to test the concept of speciation? Or are you trying to test whether two organisms can or cannot interbreed? It's like you think they're the same thing. Or maybe you think WE think they're the same thing. You probably don't even know what you think.


You see 'potential to interbreed ' the wame way anyone else would see a locomotive heading their way when they are stuck on the tracks trying to pretend that it's all about vague notions.

No. I see "potential to interbreed" as meaning two organisms can interbreed but aren't interbreeding. It's like you can't even entertain that as concept. You are probably interfertile with 90% of the women in the world, Magellan (assuming your interfertile with any of them). Does that mean you're actually interbreeding with 90% of them?

If so, you must be exhausted.


The time is fast appraoching where you will have to agree that 'potential to interbreed' is an untestable, and therefore unscientific , concept. And that means only one thing - evolution is an unscientific fantasy.

The time is fast approaching when you're so cornered on this thread that you'll have to bail on it, just like you've bailed on every other thread I've challenged you on.

[ericmurphy]

Apparently Magellan thinks it's impossible to tell if two organisms can interbreed.

If two dogs can mate and produce puppies, is it still impossible to tell if they're interfertile, Magellan?

[magellan004]

Here's a free tip - Avoid babble by starting a definition with 'XXX means ...'
So with your other lame excuse for begging the question we have -
'Species means two populations of organisms belong to the same species if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed.' - which is gobbledygook.

But anyway - you gave it another try -

Let's try this:
"Species, n: a population of organisms which are capable of interbreeding even if they do not actually, due to e.g., geographic isolation, interbreed."

That's fine.
That's a definition.
Only one problem - you dismissed it several times as meaningless.

So try again.

Species means ...

Magellan

[ericmurphy]

Here's a free tip - Avoid babble by starting a definition with 'XXX means ...'
here's a free trip: go to your local community college and see if you can register for a few English as a Second Language courses. You really seem to have some serious trouble understanding English.


So with your other lame excuse for begging the question we have -
You mean with your lame excuse for pretending you don't understand anything anyone says.


'Species means two populations of organisms belong to the same species if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed.' - which is gobbledygook.

Well, sure, for the typical speaker of Korean who speaks no English, I'm sure it is. For the other people reading this thread, I'm sure it's pretty clear what it means.


But anyway - you gave it another try -


That's fine.
That's a definition.
It's the same definition I've been using all along, Magellan. This is only about the twentieth time I've spelled it out for you.


Only one problem - you dismissed it several times as meaningless.

No. I dismissed YOUR definition—"a classification of animals which can interbreed"—as meaningless.

[ericmurphy]

I think Magellan's strategy at this point is to so blatantly misrepresent other posters' statements that he goads someone into calling him a liar, so he can then report them to the mods.

Because I cannot imagine why else he so consistently does it.

[ericmurphy]

Also—why does he continue to deny it's impossible to test whether two organisms, or even populations of organisms, can interbreed, when I've given him specific tests for ability to interbreed?

Apparently he thinks that because the results are sometimes equivocal, they're therefore always equivocal.

That would be my guess:

http://www.planet-deepblu.com/~eric/graphic_links/GrayVsBandW.png

[magellan004]

1.
No. I dismissed YOUR definition—"a classification of animals which can interbreed"—as meaningless.

2. 'Species: members of populations that actually or potentially interbreed in nature.'

You dismissed 1. as meaningless because 'Practically all animals can interbreed'.

Surely 'Practically all members of groups can interbreed' too? Which would make 2. meaningless for exactly the same reason.

What am I missing?
Or is it true that you realise you were onto something (the meaninglessness of "Species') and now want to bury your revelation in lots of random posts?

Because you are correct. All animals can interbreed so they all belong to the one Species.

Magellan

[ericmurphy]

1.

2. 'Species: members of populations that actually or potentially interbreed in nature.'

You dismissed 1. as meaningless because 'Practically all animals can interbreed'.

They can all interbreed with something, Magellan. In your typical ambiguous fashion, you fail to specify with what they can interbreed.


Surely 'Practically all members of groups can interbreed' too? Which would make 2. meaningless for exactly the same reason.

Species: a population of organisms whose members can freely interbreed with each other, regardless of whether they actually do interbreed with each other.

This is so utterly STUPID. 75 pages into this thread, you STILL haven't figured out what a freaking SPECIES is. And you think you have a prayer of ever understanding speciation?

The only purpose you serve here is to entertain us as the clown you are.


What am I missing?
A brain, maybe?


Or is it true that you realise you were onto something (the meaninglessness of "Species') and now want to bury your revelation in lots of random posts?

Maybe you're onto something, Magellan: if you pretend you don't understand a single word anyone says, eventually everyone will give up arguing with you and you'll be able to pretend you've "won."

And in the meantime, if you really believed this:


Because you are correct. All animals can interbreed so they all belong to the one Species.

Then why did you write this:



Let's try this:
"Species, n: a population of organisms which are capable of interbreeding even if they do not actually, due to e.g., geographic isolation, interbreed."
That's fine.

Now maybe you've realized your tactical error too late? You've already admitted my definition of "species" (an operational definition, for the purposes of my model) is "fine," you've changed your mind and now say the definition is "meaningless" because everything can interbreed.

Right. Mice can breed with sequoia redwood trees, which can breed with hair lice, which can breed with sea bass, which can breed with water buffalo, which can breed with sand fleas.

Maybe Magellan is having some sort of internal contest with himself to see how brain-meltingly inane he can be.

Let's see. Can we get Magellan to insist he doesn't know what an "animal" is, and therefore the term "animal" is meaningless?

[sylas]

This post gives a serious answer to the question posed in the quote just below. Before posting this, I have deliberately gone through my own reply and removed any disparaging remarks about persons. This post is intended to be exclusively substantive, if anyone wanted to take that focus.


Now, I suggest that to save typing, we call ( A difference of A + B + C ... + Z) = Factor X.

Any problem with that?

If Individual 1 has Factor X and Individual 2 does not have Factor X then Individual 1 cannot breed with Individual 2.


There are two serious problems with that.

Problem 1. Internal consistency

The first problem, easily fixed, is that it is not internally consistent. You start out by proposing Factor X to be a "difference of A+B+C+D+E+F". That is, "factor" (should we adopt that usage) is not a quality of an organism; but of a PAIR of organisms. This usage invites confusion.

The confusion shows up immediately when you speak of individual 1 having the factor and individual 2 not having the factor. That's incompatible usage with your preceding definition of the factor as being the difference.

The word "factor" is better used as some aspect of an organism; a quality it may have, or not have, or possess in different forms. That is how it has been used throughout the thread. Then, when you have two organisms, you have two factors to compare and see if they are compatible or not (or more realistically, to what degree they are compatible).

It would be better, given your sum and difference idea, to speak of the "factor X" as the sum A+B+C+D+E+F, since this is a quality of an organism. The difference of two factors then becomes the test of compatibility. This matters, since genomes and heritable characters are carried by individuals, not couples. Couples are how individuals generate new individuals.

That's the first problem fixed, without altering the key idea.

Problem 2. Biological correctness

The second problem is more serious. You are attempting to use a sum A+B+C+D+E+F as a factor in an individual. That's incorrect, in the sense of failing to match biology. The correct abstraction here is not a difference of two long sums, but a sum of many differences.

If you recognize three factors A, B, C that impact upon fertility, you cannot simply sum those (A+B+C) to get a single combined factor for comparison with other organisms. What you have to do, in general, is test each factor separately, and get a contribution from each DIFFERENCE. That is, let Ai, Bi, Ci be the various factors for individual i. To get a fertility between individuals 1 and 2, you are suggesting the difference

(A1 + B1 + C1) - (A2 + B2 + C2) < threshold
But the biologically realistic abstraction, which better captures the idea of too much difference, is as follows:

abs(A1 - A2) + abs(B1 - B2) + abs(C1 - C2) < threshold
More often a notion of Euclidean distance is used; a sum of squares.

(A1 - A2)2 + (B1 - B2)2 + (C1 - C2)2 < threshold2
It's important to have the "absolute" function, or to take squares, because otherwise you have negative differences in one factor compensating for positive differences in another. The Euclidean distance captures the idea that the total distance can only be increased by increasing the distance between individual factors.

With this model, there is no single number, or single factor, that you can calculate for each individual and then compare to test fertility. The test has to take and use three numbers from each individual; fertility in this model has three dimensions. Biological reality has a lot more than this.

No matter how you cut it, msg #1131 was incorrect. There isn't one factor. There isn't a simple sum of numbers. The people who speak of many factors being involved are correct, and anything that simplifies away from that is simplifying away from the reality of biology.


* * * * *

A concrete published example of simulation

Here is a concrete example of a simple simulation exploring a model for speciation.
Hoelzer GA et. al (2008) Isolation-by-Distance and Outbreeding Depression Are Sufficient to Drive Parapatric Speciation in the Absence of Environmental Influences (http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1000126), in PLoS Comput Biol 4(7): e1000126.

This paper uses a computer simulation with fertility of a couple modeled as a single number obtained by summing the differences in the contributing factors.
For the experiments described in this paper, the habitat across the grid environment was homogeneous, so location did not influence the fitness of individuals. However, we introduced one important dependency: the offspring's survival probability was a decreasing function of the genetic difference between merging gametic genomes. Expressing the genetic difference between two chromosomes as a fraction between 0 (nucleotide identities at all positions of the DNA sequence were identical) and 1 (nucleotide identities at all positions of the DNA sequence were different), offspring resulting from gametes with a genetic difference greater than a threshold θ had zero survival probability (we used θ = 0.6 in this study; see Materials and Methods). Conversely, gametes with a genetic difference less than θ0 were 100% compatible (we used θ0 = 0.05 in this study). The negative relationship between gamete genomic difference and offspring viability was a simple representation of Dobzhansky-Muller reproductive incompatibility. [...]

Note in particular that the paper describes the particular aspects of biology which the simulation is attempting to represent, albeit in a highly simplified form. The Dobzhansky-Muller model is not a simulation technique, but a testable biological theory about the basis for infertility of organisms with genomes that are too far different from each other. See, for example:
Orr H.A. and Turelli M. (2001) The evolution of postzygotic isolation: accumulating Dobzhansky-Muller incompatibilities. (http://www.ncbi.nlm.nih.gov/pubmed/11475044), in Evolution 55(6) pp 1085-94.

Infertility between couples arises when there are too many of these D-M incompatabilities; hence the biological justification for representing infertility in the simulation by summing differences. It is also relevant that the simulation does not simply pick a dividing point with infertility below that threshold and full fertility above it. There is a region with shades of gray, where fertility is reduced without being lost altogether. This too, is a biological reality; though you could omit it from a simulation if you wanted to test whether it matters.


[…] A happy compromise. […]

This is a third problem, and perhaps the most serious of all.

We aren't voting on this, or trying to reach a happy medium by consensus. This thread is (ostensibly) for a discussion and/or critique of models of speciation used in evolutionary biology. Several people in the thread have been giving reasonably good descriptions of the basics of those models. It is a misunderstanding or distortion of those models to think that they mean fertility can reduce to a single factor; the only way forward is to recognize the error and avoid it. The reality is that there is no single number or single factor that you can give for an individual, and then use that to test for fertility with another individual. Fertility has many dimensions.

Your suggestion of summing numbers for each individual, and then taking the difference of those two numbers, is unrealistic as a representation of biology, and the descriptions involving many factors are more correct. Actual simulations use many factors as well.

You could write a simulation using a single factor to see what happens. You might be able to get an analog of speciation in such a model, though I would expect speciation in such a case not to be persistent. With a single dimension it is much too easy for one population to regain fertility with another simply by drift. In biology and in simulations, fertility between two individuals is a consequence of many interacting factors.

If your aim is to look at models of evolutionary biology, then you have to first understand those models, and not invent or propose something different, or compromise the models by changing them to incorporate new ideas of your own.

Cheers -- sylas

[magellan004]

They can all interbreed with something, Magellan. In your typical ambiguous fashion, you fail to specify with what they can interbreed.



Species: a population of organisms whose members can freely interbreed with each other, regardless of whether they actually do interbreed with each other.

I don't think that's right.
You could have two groups (populations) of say lions. That doesn't mean there are two species of lions, surely?

And what about a lone lion - cut off from the pride? That wouldn't belong to a population and so it wouldn't belong to a Species. Or solitary dogs or male moose?

Magellan

[ericmurphy]

I don't think that's right.
That you think something is wrong is a virtual guarantee that it's right.


You could have two groups (populations) of say lions. That doesn't mean there are two species of lions, surely?

Can lions interbreed, Magellan? They can, can't they?

Let's say we have two different populations of lions which don't interbreed. Even though they can interbreed. Are they still conspecific?

Yes. They are. By my operational definition, the one I am using in my model, two populations of organisms which can interbreed with each other are conspecific even if they don't interbreed with each other.

So why do you need me to answer your question for you, Magellan? You should be able to answer it simply by looking at my operational definition of "species."


And what about a lone lion - cut off from the pride? That wouldn't belong to a population and so it wouldn't belong to a Species. Or solitary dogs or male moose?

Why can't you answer this question, Magellan? Everything in my operational definition gives you the answer. But somehow, your poor befuddled bemuddled mind just can't make head or tail of it.

I guess you'll just have to go through life not knowing.

So: back to my model. Let's start with the first step:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.


Are we clear so far? Or do you need a definition for "population"? Or for "ancestral"?

Maybe for "single"?

Probably for "interbreeding"; that one has historically been problematic for you.

How about "start"? Are we good on the meaning of "start"?

"We"? Do you know what "We"? means?

[ericmurphy]

If your aim is to look at models of evolutionary biology, then you have to first understand those models, and not invent or propose something different, or compromise the models by changing them to incorporate new ideas of your own.

Cheers -- sylas

I've warned Magellan on this point many times. It doesn't matter how many bad, wrong, mistaken models he comes up with under which speciation does or does not happen. A model is only as good as the extent to which it corresponds to reality. If his model bears no relationship to reality, it doesn't matter whether speciation does or does not occur under it.

I'm sure my model has many problems, but I imagine most of them are quantitative, not qualitative, which is why I've mostly been careful not to use actual quantities in it. I can't even estimate the amount of genetic difference it takes to guarantee no interfertility, except that we know it should be a fairly high number since we see numbers in nature like the genetic similarity between humans and mice at roughly 90% or so.

I hope Magellan is more certain that humans and mice cannot interbreed than he was about whether or not whales and mice can interbreed.

[Faid]

Short term memory loss?


No they don't.
Some do , some don't. Members of generation x in Western Australia did not interbreed with members of generation x in Tasmania.

And to save time, some members of a group interbreed, some don't. You're implied argument depends on every animal in a group regularly interbreeding with every other animal in the group; and - here's where it falls apart - any animal not in the ancestor's line dying off - not producing descendants. 'The ancestor' = the one with the interbreeding disability.


MagellanOh for the love of-

It's the individuals that interbreed that produce the next generation, you moron. No one says that every individual has to interbreed with every other individual! It's just that those who DO breed, are those who leave descendants. Those who don't, well, don't.

Not exactly rocket science, is it?

[Faid]

Magellan: 2 + 2 = 4
Eric : Still wrong.
Eric : So you still think 2 + 2 = 5?

I'll say it again for the mentally impaired -
Amniote , Chicken, Human
Amniote and Chicken - relatively few differences
Amniote and Human - relatively few differences
Human and Chicken - relatively many differences.


MagellanOh dear.

Humans and chickens ARE amniotes, Mags. Just FYI.

[Faid]

Why don't you tell us what Species means?
Defining Species as 'two organisms belong to the same species' is begging the question . What do they belong to?

'A circle is anything with shape of a circle' < --- Begging the question. This is a concept that eludes you.

'Country - two people belong to the same country if they both fly the same flag.' < --- begging the question. Does not tell us what a country is. Only tells us about two people.

Species - two organisms belong to the same species if ... < -- Does not tell us what Species is, the thing they belong to.

Now try again. Don't use the word you are defining in the definition; otherwise you will be begging the question.

Species - a species is ...

(This is basic reasoning. It's not that hard.)

MagellanSpeaking of "basic reasoning"...

Once again:

DEFINITIONS DO NOT 'BEG THE QUESTION'. DEFINITIONS ARE NOT ARGUMENTS.

Repeat that until it sinks in.

[Faid]

You did it here-
Post 1114.
Species: "two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed"

Now please give a definition of Species which does not include species in the definition.

Magellan

And here we go again. Even though I explained to Mags his faulty "reasoning" before, and he had aknowledged my response. In fact, he had agreed that a "definition" saying something like "species is species" is NOT useful, but a definition describing species by the properties that are pertinent to them (like Eric did above) IS useful.

But now he has had another case of memory loss.

(EDITED- Not playing Mags' game)

[Faid]

I'll reply to Post 1126 as soon as I can but I just want to eliminate one extremely annoying habit of yours -


Do you understand how incredibly dumb that thinking is?


Take your 'Factor A'.
1. 'Does this individual differ from that individual by A?
Yes - Result = The two individuals cannot breed.
No - Result = The two individuals can breed.
We don't need Factor B. Factor B is irrelevant. So is Factor C and Factor D and Factor E. You are talking crap.

If you mean -
1. 'Does this individual differ from that individual by A?
Yes - Result = We have to test for Factor B.
No - Result = We have to test for Factor B.
Then why bother testing for Factor A?
Factor A is irrelevant.
You are talking crap.

That level of imbecility is very difficult even for a person with the patience of an Indonesian to cope with.

From now on we will refer to the difference that matters, the difference we test for - as Factor X.

Magellan

Already addressed and explained back at page 10.

Find a new shtick, Mags, this one's getting stale.

[Faid]

I understand where you're coming from. You want to stick to your 'possibles' and probabilities. The last thing you want is to be nailed down to a testable concept.

You see 'potential to interbreed ' the wame way anyone else would see a locomotive heading their way when they are stuck on the tracks trying to pretend that it's all about vague notions.

The time is fast appraoching where you will have to agree that 'potential to interbreed' is an untestable, and therefore unscientific , concept. And that means only one thing - evolution is an unscientific fantasy.

MagellanYeah, because we all know how "unscientific" and "untestable" probabilities are.

:lol:

[Faid]

Here's a free tip - Avoid babble by starting a definition with 'XXX means ...'
So with your other lame excuse for begging the question we have -
'Species means two populations of organisms belong to the same species if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed.' - which is gobbledygook.

But anyway - you gave it another try -


That's fine.
That's a definition.
Only one problem - you dismissed it several times as meaningless.

So try again.

Species means ...

MagellanSo it DOESN'T "include 'species' in the definition" after all?

:hehe:

You're flailing around hopelessly, Mags.

[magellan004]

So it DOESN'T "include 'species' in the definition" after all?

:hehe:

You're flailing around hopelessly, Mags.

Eric came up with a new definition that didn't include Species in the definition. He saw the problem he had brought up and tried a patch-over.

Do agree that in a definition of X, one shouldn't include the word X ?
Perhaps you think it's quite OK to do that sort of thing?

Magellan

[magellan004]

Yeah, because we all know how "unscientific" and "untestable" probabilities are.

:lol:

Good.

Magellan

[Faid]

Eric came up with a new definition that didn't include Species in the definition. He saw the problem he had brought up and tried a patch-over. Are you saying that Eric had previously used a definition of species where he used species to define species? If so, please provide a link (not to what you thought he said, mind you; to what he actually said).


Do agree that in a definition of X, one shouldn't include the word X ?
Perhaps you think it's quite OK to do that sort of thing?

MagellanDidn't you read my post, Mags? Wasn't it ME that said that, in a definition ox X. one should not use X? Wasn't it also ME that explained to you the distinction between that and using the PROPERTIES that define X?

Why yes, it was. (http://www.theologyweb.com/campus/showthread.php?144614-Evolution-of-The-Beetles&p=3191388#post3191388)

So Eric's definitions are perfectly fine: They DO tell us what "species" entails. It defines the features REQUIRED to define "species". In your usual dishonest manner, you try to twist a statement of definition to a simple conditional statement, and the features defining "species" to implications or side-effects of the concept- something no one ever claimed. The Mags-ter of Ambiguity strikes again.

Ogh and don't forget repeating: "DEFINITIONS DO NOT BEG THE QUESTION".

[Faid]

Yeah, because we all know how "unscientific" and "untestable" probabilities are
Good.

MagellanThe concept of sarcasm truly eludes you, doesn't it?

[Faid]

And BTW, You still have to properly address this (http://www.theologyweb.com/campus/showthread.php?144614-Evolution-of-The-Beetles&p=3193017#post3193017) post. Thanks.

[magellan004]

You wanted me to respond to you post 935.

Wrong.
Wrong.
Wrong.
Wrong.
Wrong.
Then this -

The loss of interbreeding is certainly happening within the same 'population' - Eric's Group B - the Blue Beetles, the Blue Beetles that once could interbreed with Group A, the Brown Beetles.

The loss of interbreeding is in regard to groups A and B, Mags. Not within the individuals of each group.

In the end , none of the Group B Blue Beetles descendants can interbreed with Group A.

Two different groups, Mags.
You are wrong.
The loss of breeding ability must occur within group B. At some stage some of Group B can interbreed with Group A and at that same time the rest of Group B cannot interbreed with Group A.

Scratch it out on a pencil and paper.


Magellan

[magellan004]

Are you saying that Eric had previously used a definition of species where he used species to define species? If so, please provide a link (not to what you thought he said, mind you; to what he actually said).


Post 1114.

Magellan

[magellan004]

There are two serious problems with that.

Problem 1. Internal consistency

The first problem, easily fixed, is that it is not internally consistent. You start out by proposing Factor X to be a "difference of A+B+C+D+E+F". That is, "factor" (should we adopt that usage) is not a quality of an organism; but of a PAIR of organisms. This usage invites confusion.

The confusion shows up immediately when you speak of individual 1 having the factor and individual 2 not having the factor. That's incompatible usage with your preceding definition of the factor as being the difference.
Whatever you are smoking, I don't want it.


'The confusion shows up immediately when you speak of individual 1 having Factor X and individual 2 not having Factor X.'
That makes Factor X The Difference.

Whatever it is you are puffing, I wish you'd give it up.

Magellan

[magellan004]

Yes. They are. By my operational definition, the one I am using in my model, two populations of organisms which can interbreed with each other are conspecific even if they don't interbreed with each other.


You define a Species as One Population -

Species: a population of organisms whose members can freely interbreed with each other.

Species = One population = One group.
Therefore two populations = at least two Species.

Time for you to pull another definition of Species out of your Hat. So far they your definitions have been , in your words, meaningless.

Species means ... ?

Magellan

[sylas]

S'okay; Magellan. Just ignore me. Whether it is my fault or yours, you are clearly not getting anything of value from my posts. I'll keep posting anyway from time to time, since you and I are not the only ones here involved. I take no offense at your evaluations of my contributions; be as critical as you like. Substantive criticism would be nice also; but that seems not to be your forte.

Adios -- sylas

[Faid]

You wanted me to respond to you post 935.

Wrong.
Wrong.
Wrong.
Wrong.
Wrong.
Then this -




You are wrong.
The loss of breeding ability must occur within group B. At some stage some of Group B can interbreed with Group A and at that same time the rest of Group B cannot interbreed with Group A.

Scratch it out on a pencil and paper.


MagellanNo need, as you once again failed to comprehend basic English.

Despite your pathetic obfuscating attempts, the word "INTERbreeding" has a very specific meaning.

An organisml does not simply "interbreed". That sentense means absolutely nothing.

An organism "inderbreeds" WITH ANOTHER organism.


Loss of interbreeding does not happen between the individuals of the same group.

Loss of interbreeding capability happens between the individuals of the two groups.

Yes or No, Mags? And why?

Use little stick figures if it helps.

[Faid]

Are you saying that Eric had previously used a definition of species where he used species to define species? If so, please provide a link (not to what you thought he said, mind you; to what he actually said).Post 1114.

MagellanNope, no such statement in that post. Please provide quote and explanation.

(IOW, 'bluff called').

[Faid]

Whatever you are smoking, I don't want it.


'The confusion shows up immediately when you speak of individual 1 having Factor X and individual 2 not having Factor X.'
That makes Factor X The Difference.

Whatever it is you are puffing, I wish you'd give it up.

MagellanHere's a question even a child could answer:

Suppose we call Factor X "difference of A+B+C+D+E+F". You have already agreed we can do that.

Now, imagine we have two organisms that differ in A, B, C, D, E and F.

Which of the two organisms has "factor X"?

Straight answer, please.

[Faid]

You do understand that groups can contain groups, don't you Mags?

Nah, prolly not.

[Faid]

S'okay; Magellan. Just ignore me. Whether it is my fault or yours, you are clearly not getting anything of value from my posts. I'll keep posting anyway from time to time, since you and I are not the only ones here involved. I take no offense at your evaluations of my contributions; be as critical as you like. Substantive criticism would be nice also; but that seems not to be your forte.

Adios -- sylasYou should see that as a compliment, sylas. Mags finds it exceedingly difficult to find something in your posts to twist, obfuscate and equivocate on, so he just tries to shoo you away with his posts. Not bad.

[ericmurphy]

Eric came up with a new definition that didn't include Species in the definition. He saw the problem he had brought up and tried a patch-over.

I didn't come up with a "new definition," Magellan; I've been using exactly the same definition for the entirety of this thread. I didn't "see" any "problem"; I was making fun of you for thinking a definition is self-referential if the word you're defining is even in the sentence you define it in.


Do agree that in a definition of X, one shouldn't include the word X ?
In the same sentence? No; no one agrees with that.

To Magellan, "a bicycle is a two-wheeled human-powered conveyance" is an improper definition because the word "bicycle" appears in the sentence. Maybe it has to be on a different page if it's in a book.


Perhaps you think it's quite OK to do that sort of thing?

I'm surprised Magellan thinks it's okay even to mention the word you're trying to define.

[ericmurphy]

Are you saying that Eric had previously used a definition of species where he used species to define species? If so, please provide a link (not to what you thought he said, mind you; to what he actually said).

Didn't you read my post, Mags? Wasn't it ME that said that, in a definition ox X. one should not use X? Wasn't it also ME that explained to you the distinction between that and using the PROPERTIES that define X?

Why yes, it was. (http://www.theologyweb.com/campus/showthread.php?144614-Evolution-of-The-Beetles&p=3191388#post3191388)

So Eric's definitions are perfectly fine: They DO tell us what "species" entails. It defines the features REQUIRED to define "species". In your usual dishonest manner, you try to twist a statement of definition to a simple conditional statement, and the features defining "species" to implications or side-effects of the concept- something no one ever claimed. The Mags-ter of Ambiguity strikes again.

Ogh and don't forget repeating: "DEFINITIONS DO NOT BEG THE QUESTION".

It's even dumber than that. Magellan thinks it's impermissible to use the word you're defining anywhere in the same sentence the definition is in.

[ericmurphy]

You wanted me to respond to you post 935.

Wrong.
Wrong.
Wrong.
Wrong.
Wrong.
Then this -




You are wrong.
The loss of breeding ability must occur within group B. At some stage some of Group B can interbreed with Group A and at that same time the rest of Group B cannot interbreed with Group A.

Scratch it out on a pencil and paper.

You never get less retarded, Magellan. There is no loss of fertility among the members of either group. There is a loss of fertility between members of different groups. This has been explained to you over and over and over again. But you don't actually construct a contrary argument. You simply declare it's not true.

[ericmurphy]

Post 1114.

Magellan

This is the definition of "species" I gave in post 1114:


Two populations of organisms are conspecific if they are actually capable of interbreeding, regardless of whether or not they actually do interbreed

So according to Magellan, this definition says, "two organisms are the same species if they're the same species."

[ericmurphy]

Whatever you are smoking, I don't want it.

Magellan tries to limit his contact with observational reality.



'The confusion shows up immediately when you speak of individual 1 having Factor X and individual 2 not having Factor X.'
That makes Factor X The Difference.

Whatever it is you are puffing, I wish you'd give it up.

It's hard when your idiot delusions keep colliding with reality. But the solution is simple, Magellan: bail on the thread.

[ericmurphy]

You define a Species as One Population -


Species = One population = One group.
Therefore two populations = at least two Species.

Time for you to pull another definition of Species out of your Hat. So far they your definitions have been , in your words, meaningless.

Species means ... ?

Magellan

Stop it, Magellan. You know you're toast; you know your "arguments" are a joke; you know you can't address my model; you know you can't even understand my model. All you're left to do is to make stupid, inane quibbles about definitions.

Two organisms are members of the same species if they can interbreed, regardless of whether they do interbreed. And now you're going to start the same old stupidity about, "What if one of them is sterile? Does that mean they're different species?" when we've already been over this a million times.

And to make matters worse, you keep insisting on some sort of precise, rigorous definition of "species" when we've already told you a million times evolutionary theory predicts there will be no precise definition of "species"!

Seriously, Magellan: how many times were you dropped on your head as an infant? Are you really this brain-damaged, or are you just pretending?

[sylas]

You should see that as a compliment, sylas. Mags finds it exceedingly difficult to find something in your posts to twist, obfuscate and equivocate on, so he just tries to shoo you away with his posts. Not bad.

:lol: -- yes, maybe so.

I think I am a bit of a cold fish. Compliments, insults or other personal remarks I don't find particularly interesting or useful. Compliments are embarassing, insults usually just leave me embarassed for the other person; or cross with myself if I'm the insulter. This thread, by the way, is excruciating..... :eww:

I do get a huge kick out of someone saying thanks for a post that is useful, and there's a dash of vanity in that. Similarly, if I have actually hurt someone with my posts I feel terrible. I appreciate being told firmly when I've made some kind of dumb mistake; and I aim to recognize and fix my own errors as quickly as possible, and in open forum. Genuine help in that is always welcome.

The point is that those kinds of responses are to the material rather than the person. If someone thinks I have made a mistake, while I continue to think their correction is the error; we can still have a useful discussion clarifying the point of disagreement. That's achieved when each participant is able to paraphrase accurately the viewpoint they are disputing. This is a very useful goal to have for a debate between opposing viewpoints. Agreement is not necessary to achieve this goal.

And with that, I think I can promise my next post will be on substantive biological questions again; rather than on individual quirks of participants or more meta-nonsense on what I like in posts....

Cheers -- sylas

[ericmurphy]

So, getting back to my model, Magellan: let's take it one step at a time.



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.


Are we good so far?

Can we at least get as far as "We"? The first word? Are we okay on the definition of "We"? Or do I have to define "we" without having the word "we" appear anywhere in the same post as the definition?

[magellan004]

S'okay; Magellan. Just ignore me. Whether it is my fault or yours, you are clearly not getting anything of value from my posts. I'll keep posting anyway from time to time, since you and I are not the only ones here involved. I take no offense at your evaluations of my contributions; be as critical as you like. Substantive criticism would be nice also; but that seems not to be your forte.

Adios -- sylas

Everyone is welcome in this thread - the tall , the short, the long , the wrong.

I've met heaps of people who think 'You don't understand it' is some sort argument. If you are interested in finding out why it isn't much chop I'd be happy to explain.

Magellan

[magellan004]

Loss of interbreeding does not happen between the individuals of the same group.

Loss of interbreeding capability happens between the individuals of the two groups.

Yes or No, Mags? And why?

Use little stick figures if it helps.

On day one in Group B every individual has the same interbreeding ability.
On day two in Group B one individual has less interbreeding capacity than the other Group B individuals.
On day n in Group B some individuals have a certain interbreeding capacity and certain other individuals have less interbreeding capacity.

The silly thing is - this loss of capacity is in relation to Group A individuals which the Group B individuals have no contact with. It's like Eric (example) who has never had contact with Aborigines, one day having a child that cannot breed with aborigines.

Bizarre.

Magellan

[ericmurphy]

Everyone is welcome in this thread - the tall , the short, the long , the wrong.

I've met heaps of people who think 'You don't understand it' is some sort argument.


You've also met people who make an argument, explain it in detail, support it with empirical evidence, present illustrations and diagrams to explain it in further detail, and then when you still don't even get what their argument is, let alone actually present coherent objections to it, then say "you don't understand it."

And after meeting you, I can certainly say I've met at least one person who thinks making an assertion is some sort of argument.


If you are interested in finding out why it isn't much chop I'd be happy to explain.

Whenever Magellan says, "I'd be happy to explain," what that really means is that he cannot explain.

[ericmurphy]

On day one in Group B every individual has the same interbreeding ability.
On day two in Group B one individual has less interbreeding capacity than the other Group B individuals.
On day n in Group B some individuals have a certain interbreeding capacity and certain other individuals have less interbreeding capacity.

Aside for your ludicrous silliness of equating generations with days, here how it really goes:

In generation one in group B every individual has the same interbreeding ability with other members of group B.
In generation two in group B every individual has the same interbreeding ability with other members of group B.
In generation three in group B every individual has the same interbreeding ability with other members of group B.
…
In generation 100,001 in group B every individual has the same interbreeding ability with other members of group B.
In generation 100,002 in group B every individual has the same interbreeding ability with other members of group B.

That interbreeding ability with group A may decline over the same time period doesn't change that simple fact. Interbreeding within the population does not change.

And since no interbreeding with group A is happening anyway, decreased interbreeding ability with group A carries no selective disadvantage.

This has only been pointed out to you a dozen times now.


The silly thing is - this loss of capacity is in relation to Group A individuals which the Group B individuals have no contact with.
That's not what makes it "silly"; it's what makes it irrelevant.


It's like Eric (example) who has never had contact with Aborigines, one day having a child that cannot breed with aborigines.

Bizarre.

"Bizarre"? No. It's what makes speciation possible.

[magellan004]

Nope, no such statement in that post. Please provide quote and explanation.

(IOW, 'bluff called').

This might help -
Some dictionaries define Species as a classification of animals that can interbreed.
Eric - 'That's meaningless. All animals can interbreed.'
Magellan - So what is a Species?
Eric - 'A Species is two populations that are in the same species if they can interbreed.'
Magellan - 'That's using Species to define Species and it doesn't make grammatical sense.'
Eric - '$%^&5$34*'
Eric - 'Species means a population that can interbreed.'
Magellan - 'What about animals not in a group?'
etc.

after a few days ...

No closer to working out what Species means.

Here's the most useful dictionary definition I have found -
Species - a kind of animal.

Magellan

[magellan004]

Here's a question even a child could answer:

Suppose we call Factor X "difference of A+B+C+D+E+F". You have already agreed we can do that.

Now, imagine we have two organisms that differ in A, B, C, D, E and F.

Which of the two organisms has "factor X"?

Straight answer, please.

The different one.

Magellan

[magellan004]

So, getting back to my model, Magellan: let's take it one step at a time.



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.


Are we good so far?

Can we at least get as far as "We"? The first word? Are we okay on the definition of "We"? Or do I have to define "we" without having the word "we" appear anywhere in the same post as the definition?

I'm always happy to go back to basics.
I'd suggest we go with -



We start with a single, freely-interbreeding ancestral group of individuals ; let's call them Group A. All members of this group can interbreed with each other.


I'd also suggest that whatever happens to Group A should be able to be (conceptually) modelled in a computer program. This is to avoid vague claims such as 'Z was less fit than Y'.
I suggest this so that there are clear criteria and tests.


Magellan

[ericmurphy]

This might help -
Some dictionaries define Species as a classification of animals that can interbreed.
Eric - 'That's meaningless. All animals can interbreed.'
Magellan - So what is a Species?
Eric - 'A Species is two populations that are in the same species if they can interbreed.'
Did you hallucinate this statement from me, Magellan? Because I've never said anything like it. It's still a valid definition of the term "species," though, if you take off the weirdness at the beginning. "Two population of organisms are the same species if they can interbreed."

It's not unusual for creationists to quote-mine, but you actually and regularly misquote.



Magellan - 'That's using Species to define Species and it doesn't make grammatical sense.'

So your objection (which, again, is directed at a statement I never actually made) is about my grammar?

Is this science, or literary criticism?


Eric - '$%^&5$34*'
Is this another misquote? Another false statement about what I said?


Eric - 'Species means a population that can interbreed.'
Magellan - 'What about animals not in a group?'
etc.

after a few days ...

No closer to working out what Species means.

YOU'RE not closer to figuring out what it means. No one else seems to have trouble with it.

And again, for the terminally stupid: I've been telling you for MONTHS that evolutionary theory PREDICTS it will be difficult to define the term "species."

Every time you complain about definitions of species, you further confirm evolutionary theory and drive yet another nail into the coffin of speciation creation.

But then, you never learn, do you?


Here's the most useful dictionary definition I have found -
Species - a kind of animal.

Since I've already given you exactly the operational definition I'm using in my model, over and over again, it's clear you're just squirting squid-ink, trying to cover up the fact that you can come up with no legitimate objection to my model.

So let's try again:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.


And just for the record, Magellan, the word "species" does not even appear in my model of how speciation happens. So you can stop whining and crying about how you cannot figure out what the word "species" means.

[ericmurphy]

The different one.

Magellan

Hey Magellan: What's the difference between a duck?

[ericmurphy]

I'm always happy to go back to basics.
You mean, you're always happy to confuse things to the maximum extent possible.



I'd suggest we go with -



We start with a single, freely-interbreeding ancestral group of individuals ; let's call them Group A. All members of this group can interbreed with each other.


Well, of course you would, Magellan. Why? Because the term "Group A" is already in use. You'd love to be able to refer to two different groups by the same name to maximize the confusion and ambiguity.

What's your objection to referring to the original group as group X, and then the two subsequent groups as A and B? Because it would be confusing to refer to two different groups by two different names?


I'd also suggest that whatever happens to Group A should be able to be (conceptually) modelled in a computer program. This is to avoid vague claims such as 'Z was less fit than Y'.
I suggest this so that there are clear criteria and tests.

The last thing you want is clear criteria and tests.

I've already explained how a computer simulation would model the process. Conceptually it would be identical to my model.

So far: another post by Magellan that makes it clear he can't even get past the first step in my model. So let's try it again:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.


Have you figured this part out yet? Can you tell me what your objection is to referring to this original ancestral population as 'X'?

[ericmurphy]

The fact of the matter is, Magellan claimed no one could tell him how speciation happens. He's been given a clear, concise, easy-to-understand (by people with room-temperature IQs, anyway) model for how evolution happens, thus refuting his claim.

He can't find any problems with that model. He gives no indication he even comprehends the model. Instead, he makes the following hare-brained assertions:


It is impossible to tell if two organisms can interbreed
It is impossible to tell if two organisms are the same species
There is no such thing as a species
You can't define a word using a sentence that includes the word you're defining
Given objects A and B, B can be different from A without A being different from B
You can't use words to describe things

[magellan004]

Well, of course you would, Magellan. Why? Because the term "Group A" is already in use.

'Population' is already in use - it has the odour tench of 'Species' about it.
So your suggestion is out.
I'll use 'A Group of Individuals'.

1. We start with Group A (They used to be called Brown Beetles).
2. Group A is physically split into two groups - Group A and Group B.
3. Immediately after the split all members of Group A and Group B can all interbreed with all other members of Group A and group B.
4. Some of the members of each group have children. On average one generation per year. Any child of Group B parents will be different to its parents. A child is born with its own new differences and also the differences of its parents.
5. Individuals only have one breeding season.

Later -
6. Group A individuals are similar to the original Group A individuals. No detectable differences.
7. Group A and Group B are brought together.
8. Observation shows that members of Group A cannot breed with Group B.

The question is - if this situation came about through evolutionary processes could a computer program simulate evolutionary processes that lead to the outcome in 8. above?

If a computer program could simulate the evolutionary processes then the computer program must have a rule for determining whether an individual from Group B can interbreed with an individual from Group A.

That rule would have to test one individual at a time. That rule would have to give a Yes/No answer - 'Yes, this individual is capable of breeding with Group A' or 'No, this individual is not capable of breeding with Group A'.

That rule would have to be an arbitrary rule along the lines of 'If Individual 1 possesses X and Individual 2 does not possess X then Individual 1 cannot breed with Individual 2.'

Let's say that at the start no individual possessed X.
Then-
At the end no Group A member will possess X.
By Step 8. all Group B members possess X.
By step 8. every Group B member has to be a descendant of the first individual to possess X.
By step 8 no Group B individual can give birth to a 'Non-X' child.

We can draw a few conclusions about the properties of this 'Factor X'.

Which, debate about definition of species aside, we can now address.

Magellan

[ericmurphy]

'Population' is already in use - it has the odour tench of 'Species' about it.

So now we can't use words that have ever been used before.


So your suggestion is out.
Uh, no. It's my model, it's my words.


I'll use 'A Group of Individuals'.

You're not using anything. It's my model. You don't have a model of how speciation happens. You don't even believe speciation does happen. And again, it doesn't matter how many bad, wrong, broken, stupid models you come with, and whether or not speciation does or does not happen under those models. There is one model under discussion: mine.


1. We start with Group A (They used to be called Brown Beetles).
No we don't. We start with an ancestral population X.


2. Group A is physically split into two groups - Group A and Group B.
Right, so now there are two group As. Great going, genius.


3. Immediately after the split all members of Group A and Group B can all interbreed with all other members of Group A and group B.
Which group A? The first group A, or the second group A?


4. Some of the members of each group have children.

How many groups are there? One, or two? Or three? Do you know? You have a group A, a group A, and a group B. How many groups is that?


On average one generation per year. Any child of Group B parents will be different to its parents. A child is born with its own new differences and also the differences of its parents.
5. Individuals only have one breeding season.

This moron is determined to continue with his "model" no matter what.
Let's try again:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.


No one's going to discuss your model, Magellan.

[ericmurphy]

And, you know, for a guy who keeps saying time is "irrelevant" to speciation, he sure spends a lot of time telling us how long a generation lasts, and how many breeding seasons there are in a year. He very significantly points out in 4. that there is "on average one generation per year" and then in 5., "individuals have only one breeding season." (I wonder if that means individuals only breed once a year, or if it means they only breed once ever. I know it's pointless to even ask Magellan, since he undoubtedly has no idea what his own "model" says.)

Given the irrelevancy of time in your "model," why do you think any of that matters, Magellan? Is it in there because it makes your "model" look "science-y"?

It's also entertaining that under Magellan's "model," Group B individuals mutate while apparently neither group A nor group A mutate. I wonder how he accounts for that.

[ericmurphy]

Here's the model that is under discussion:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.
Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.

[ericmurphy]

And before Magellan claims it's his "model" that's being discussed in this thread, let's look at his OP:


I would like to introduce you to The Beetles. These little guys are going to walk us through a hypothetical simulation of evolution.

It all started in Year tx with about 10 brown Beetles living on an island that had no other beetles but was very close to the mainland.
These Beetles produce children about once a year and only have one breeding season..
Each beetle has an identifier on it which shows names of its two parents and their parents etc. . This identifier system is passed on to children so the ‘first generation’ children have a record or their own parents (the tx generation) and their parent’s parents etc.

Millions of years later , in say year ty, there are 20 Beetles.
Professor Smithers Bones examines all of the Beetles There are some brown Beetles. The rest are green.
He can trace each beetle back through time.

But something puzzles the good Professor- Have these Beetles evolved and are there different 'Species' of Beetles?

Any ideas how we might answer these questions?


Magellan

[Faid]

On day one in Group B every individual has the same interbreeding ability."Interbreeding" with who?

On day two in Group B one individual has less interbreeding capacity than the other Group B individuals."Interbreeding" with who?

On day n in Group B some individuals have a certain interbreeding capacity and certain other individuals have less interbreeding capacity."Interbreeding" with who?


The silly thing is - this loss of capacity is in relation to Group A individuals which the Group B individuals have no contact with.Good. And you think that's a problem because...?
It's like Eric (example) who has never had contact with Aborigines, one day having a child that cannot breed with aborigines.
Um, no. That makes even less sense than usual. Are you trying to confuse us with some weird Lamarkian concept now? Are you pretending that anyone has ever said that, if we put a wall between two lab mice and prevent them from having contact, those specific individual mice will have children that don't interbreed? Are you losing it, or just jumping the shark?

Why don't you respond to the actual points explained in my posts?

Bizarre.What's going in your head is bizarre (assuming you're not just pretending).

[Faid]

The different one.

Magellan

You're joking, right?

Mags, if organism A is different to B, is it possible for B NOT to be different to A?

Are you playing some kind of game, like "let's see how stupid I can get before they give up on me"? Sure looks like it.

[Faid]

This might help -
Some dictionaries define Species as a classification of animals that can interbreed.
Eric - 'That's meaningless. All animals can interbreed.'
Magellan - So what is a Species?
Eric - 'A Species is two populations that are in the same species if they can interbreed.'
Magellan - 'That's using Species to define Species and it doesn't make grammatical sense.'
Eric - '$%^&5$34*'
Eric - 'Species means a population that can interbreed.'
Magellan - 'What about animals not in a group?'
etc.

after a few days ...

No closer to working out what Species means.

Here's the most useful dictionary definition I have found -
Species - a kind of animal.

Magellan

No links and quotes to what Eric ACTUALLY said, in post #1114 or anywhere else. So no, it doesn't "Help". Try again.


(IOW, desperate evasion noted and ignored).

[ericmurphy]

Good. And you think that's a problem because...? Um, no. That makes even less sense than usual. Are you trying to confuse us with some weird Lamarkian concept now? Are you pretending that anyone has ever said that, if we put a wall between two lab mice and prevent them from having contact, those specific individual mice will have children that don't interbreed? Are you losing it, or just jumping the shark?

I cut Magellan some slack on this point and assumed he was talking about Eric one day having a descendant unable to interbreed with Aborigines. But Faid's probably right. Magellan probably does believe humans can speciate in a single generation.

Except that he doesn't believe speciation happens at all, ever. But then, consistency was never Magellan's forte. I'm still trying to figure out what his forte is.

[magellan004]

I cut Magellan some slack on this point and assumed he was talking about Eric one day having a descendant unable to interbreed with Aborigines. But Faid's probably right. Magellan probably does believe humans can speciate in a single generation.

Except that he doesn't believe speciation happens at all, ever. But then, consistency was never Magellan's forte. I'm still trying to figure out what his forte is.

For some odd reason Faid thinks you grew up in the Australian outback. Did you?

Magellan

[magellan004]

Here's the model that is under discussion:

[LIST=1]
We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.
Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences [i]within a population).

No . That last point is just guesswork. Mathematics shows it's not true.
It's quite possible for the differences between some members of A and B to be less than the differences between some to members of B and other members of B.

The bigger Group B gets the more this will be so.

Therefore using you model speciation cannot occur (unless there are hidden factors).

Magellan

[ericmurphy]

For some odd reason Faid thinks you grew up in the Australian outback. Did you?

Magellan

For some unfathomable reason Magellan thinks Faid thinks I grew up in the Outback. Can you give us some insight into why you would think that, Magellan? Maybe you think Faid thinks you were saying I grew up around Aborigines and hence would have to be isolated from them before I could magically have a child who couldn't interbreed with Aborigines?

Is that what you "think," Magellan? If "thinking" isn't too grand a term for what happens between your ears?

[ericmurphy]

No . That last point is just guesswork.
It's a freaking model, Magellan. I keep hammering that point into your head with a length of rebar, but it just doesn't seem to penetrate.

We might, someday, get to the point where we actually try to figure out how close to reality this model is. But at the rate we're going, we're never going to get there. You simply cannot make head or tail out of this model—or even seem to realize it is a model—despite its striking simplicity. How you ever think you'll be able to investigate how valid it is is something of a mystery.


Mathematics shows it's not true.
You don't have any mathematics, Magellan. You seem to think that if you refer to some object or concept by a letter, that makes it mathematics. There is nothing you've said that even remotely calls into question this model. And again, since you don't understand the model, there's no way you can critique it.


It's quite possible for the differences between some members of A and B to be less than the differences between some to members of B and other members of B.

No it's not. Selection pressures prevent divergence in freely-interbreeding populations. Another point that's been hammered into your noggin with a twelve-pound sledge.

Seriously, Magellan: at least come up with some new objections. Trying the same, tired, oft-blown-away objections does nothing but demonstrated your own utter cluelessness.


The bigger Group B gets the more this will be so.

No. Bigger groups generally have less diversity, and fewer deleterious mutations (which by definition reduce fertility) than small ones. Once again, your utter cluelessness and ignorance trips you up.


Therefore using you model speciation cannot occur (unless there are hidden factors).

Of course it can. And nothing you have said in 80 pages casts the slightest doubt on the assertion that it can.

What are your objections to this model so far?


That "mathematics" contradicts it: FALSE. What "mathematics"?
That differences between non-interbreeding populations are smaller than within interbreeding populations: FALSE. You forgot selection pressures, as usual
That larger Nes have greater diversity than smaller ones: FALSE. Deleterious mutations are eradicated more quickly from larger populations than from smaller ones.

[sylas]

Here's the model that is under discussion:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, colonization of an island by either subpopulation, or even a genetic event like polyploidy or chromosomal fission or fusion.
Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.


Very clear, Eric; but there's one issue to fix in your step 3. You need to remove the aside on genetic events in that step.

The essential point about geographical isolation in your model is that it serves as a hard barrier to geneflow which can later be removed. Speciation corresponds to development of a hard barrier to gene flow that has become fixed between the populations (described in step 7). The ultimate barrier in your model is persistent and intrinsic to the populations; the initial barrier is ephemeral and may be added or removed from time to time.

In this allopatric speciation model, you can't use use a genetic event as the initial breeding barrier. A genetic event would either serve to restrict geneflow from the start, or it doesn't serve to isolate the two populations from each other. In either case, it doesn't match step 2.

Cheers -- sylas

[ericmurphy]

Very clear, Eric; but there's one issue to fix in your step 3. You need to remove the aside on genetic events in that step.

Why does it have to be removed? Can't genetic events like polyploidy result in reproductive isolation equivalent to that formed by physical barriers? I mean, I'm happy to remove it—it's not necessary for the model to work—but I was trying to make the model as general as possible without making it too difficult to follow.


The essential point about geographical isolation in your model is that it serves as a hard barrier to geneflow which can later be removed. Speciation corresponds to development of a hard barrier to gene flow that has become fixed between the populations (described in step 7). The ultimate barrier in your model is persistent and intrinsic to the populations; the initial barrier is ephemeral and may be added or removed from time to time.

So the point being that a fusion or polyploidy is a permanent (or at least for all intents and purposes permanent) barrier?


In this allopatric speciation model, you can't use use a genetic event as the initial breeding barrier. A genetic event would either serve to restrict geneflow from the start, or it doesn't serve to isolate the two populations from each other. In either case, it doesn't match step 2.

Okay, I see what you mean. It would make more sense to have two models, an allopatric model (which most of mine corresponds to) and a sympatric model, without commingling the two. I can deal with that. That makes the model:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, or colonization of an island by either subpopulation.
Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.


That was easy enough.

[magellan004]

Maybe you think Faid thinks you were saying I grew up around Aborigines and hence would have to be isolated from them before I could magically have a child who couldn't interbreed with Aborigines?

Yes, almost -

It seems that Faid thinks what I was saying was -

(For example) Eric grew up around Aborigines and got isolated from them before Eric magically had a child who couldn't interbreed with Aborigines.

You and I know that no one in their right mind could arrive at that from what I said. Unfortunately he won't listen to either of us.

Magellan

[magellan004]

1. Selection pressures prevent divergence in freely-interbreeding populations.
2. Bigger groups generally have less diversity, and fewer deleterious mutations (which by definition reduce fertility) than small ones.

Instead of insisting - show.
Show how, using explicit processes and tests, that these assertions of yours must happen in your model.

Magellan

[ericmurphy]

Yes, almost -

If you really think that (and aren't just joking), you have to be one of the least clued-in people I have ever had the dubious pleasure of interacting with online.


It seems that Faid thinks what I was saying was -

(For example) Eric grew up around Aborigines and got isolated from them before Eric magically had a child who couldn't interbreed with Aborigines.

No, Magellan, that's what you thought Faid thought. That's why you asked him if he thought I grew up in Western Australia.


You and I know that no one in their right mind could arrive at that from what I said. Unfortunately he won't listen to either of us.

Actually, that's the most straightforward conclusion; that you thought Faid thinks I grew up in Australia. You apparently believe the sort of "isolating event" we've been talking about here results in individuals themselves losing the ability to interbreed with other individuals.

But it's hard to know what you think, since you yourself don't seem to really know what you think.

[sylas]

Why does it have to be removed? Can't genetic events like polyploidy result in reproductive isolation equivalent to that formed by physical barriers? I mean, I'm happy to remove it—it's not necessary for the model to work—but I was trying to make the model as general as possible without making it too difficult to follow.

Too general is not always a good thing. There are different ways in which speciation may occur and they have different models; as you also say at the end of this post.

My point is simply that your step 2 says that all individuals in A and B are interfertile with each other. A genetic event CAN be isolating; but your step 2 specifies it is not; this introduces an internal inconsistency in the description.

Additionally, genetic events arise not in populations, but in individuals. It takes time to spread through to a non-trivial number of other individuals; and that is highly unlikely to occur if there is any significant reduction in fertility associated with having parents that are heterogeneous with respect to this change.

The problem is removed with the change you have made at the end of this post.

Cheers -- sylas

[ericmurphy]

Instead of insisting - show.
Show how, using explicit processes and tests, that these assertions of yours must happen in your model.

Magellan

When you've actually figured out what my model asserts, then we can talk about evidence that it comports with reality.

I'm not going to spend a lot of time finding evidence to support a model you don't comprehend in the first place.

And let's not forget; you didn't ask for evidence that a particular model actually comports with reality. You asked for a model that can explain reality. Eighty pages later, you still can't figure that model out.

I'm sick of creationist goalpost-shifting. First they claim you have no explanation for something. Then, after you give them an explanation, they pretend what they wanted all along was proof that the explanation is actually correct.

Learn the model. Then try to criticize it.

[ericmurphy]

Too general is not always a good thing. There are different ways in which speciation may occur and they have different models; as you also say at the end of this post.

Agreed. A too-general model is only going to be valid in the areas where it actually applies.


My point is simply that your step 2 says that all individuals in A and B are interfertile with each other. A genetic event CAN be isolating; but your step 2 specifies it is not; this introduces an internal inconsistency in the description.

Yes. After all, in steps 4 and 5, differences accumulate and interfertility declines. But if we include something like polyploidy as a barrier to interbreeding in step 3, then steps 4 and 5 are superfluous.


Additionally, genetic events arise not in populations, but in individuals. It takes time to spread through to a non-trivial number of other individuals; and that is highly unlikely to occur if there is any significant reduction in fertility associated with having parents that are heterogeneous with respect to this change.

It's less tricky with organisms which produce larger numbers of offspring in a single generation (it wouldn't be that rare for two individuals out of a thousand offspring both to be tetraploid in an otherwise diploid population), but yes, overall sympatric speciation is probably much rarer than the allopatric kind.

See, Magellan? Constructive criticism that actually improves the model. Unlike your suggestion that we replace 'X' with 'A,' giving us two distinct groups both referred to by the same name.

[magellan004]

We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, or colonization of an island by either subpopulation.
Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.


That was easy enough.

Good. At last you got rid of 'Genetic events'. But we had already agreed that we only needed a geographical split for the purposes of your model.

Maybe later we could take a look at your zany notion of 'genetic events' and 'splitting'.

Magellan

[ericmurphy]

Good. At last you got rid of 'Genetic events'.
Like it was even a big deal having it in there. And you still don't understand why it was in there, or why it makes sense to take it out. You still don't know what polyploidy or chromosomal fusion even are.


But we had already agreed that we only needed a geographical split for the purposes of your model.

Which is why I have no problem removing it.


Maybe later we could take a look at your zany notion of 'genetic events' and 'splitting'.

Sure. In a few hundred years, when you have finally developed a basic understanding of how my model works in the first place.

[sylas]

Good. At last you got rid of 'Genetic events'. But we had already agreed that we only needed a geographical split for the purposes of your model.

Actually, this does not get rid of genetic events; they are an essential aspect of all speciation models. The proper place for genetic events is step 4. A "genetic event" is something which introduces a change to the genome that is completely new; not inherited from either parent. Step 4 is the accumulation of such changes over time. Many many genetic events are involved; they are essential for the model to work.

Look at step 4. They are still there, in their proper place, as they have been throughout the entire thread. There is no speciation without them.

The issue Eric and I have just discussed and resolved (in the space of two or three posts!) concerns an addition made to the model to allow for genetic events at step 3 as the initial isolating mechanism. This didn't work, for reasons covered in those two or three posts. It was added as an attempt to make the model more general, but didn't succeed in that respect. By removing it, Eric has returned to a more faithful summary of the model which he has been using from the start, and which is a faithful description of the basic allopatric speciation model used in evolutionary biology.

A common error in this thread, repeated again and again and again, is the attempt to have one single step as the genetic isolating mechanism. Isolation of populations in a single generation doesn't happen that way. Infertility between populations doesn't arise that way*. Trying to add those steps has been an error, no matter where it comes from.

Usually, it's been you. The major difference is that after well over a thousand posts, there seems to have been little progress in getting you to understand and address the models used in evolutionary biology. If you are now going to be able to drop the notion of a sharp dividing line; a single factor; a one generation step in which the speciation suddenly occurs, then you will have made enormous strides in elementary comprehension -- an essential first step required before a coherent critique can even be expressed.

Cheers -- sylas

*Note that a single generation event can isolate one individual. Not a whole population. This is the basis of some kinds speciation in plants. For example, by polyploidy (doubling of the chromosome number in one generation) as can occur with plants; though not to my knowledge with animals. (If anyone knows an example, however, let me know!)

[magellan004]

Actually, this does not get rid of genetic events; they are an essential aspect of all speciation models. The proper place for genetic events is step 4. A "genetic event" is something which introduces a change to the genome that is completely new; not inherited from either parent. Step 4 is the accumulation of such changes over time. Many many genetic events are involved; they are essential for the model to work.

Look at step 4. They are still there, in their proper place, as they have been throughout the entire thread. There is no speciation without them.

The issue Eric and I have just discussed and resolved (in the space of two or three posts!) concerns an addition made to the model to allow for genetic events at step 3 as the initial isolating mechanism. This didn't work, for reasons covered in those two or three posts. It was added as an attempt to make the model more general, but didn't succeed in that respect. By removing it, Eric has returned to a more faithful summary of the model which he has been using from the start, and which is a faithful description of the basic allopatric speciation model used in evolutionary biology.

A common error in this thread, repeated again and again and again, is the attempt to have one single step as the genetic isolating mechanism. Isolation of populations in a single generation doesn't happen that way. Infertility between populations doesn't arise that way*. Trying to add those steps has been an error, no matter where it comes from.

Usually, it's been you. The major difference is that after well over a thousand posts, there seems to have been little progress in getting you to understand and address the models used in evolutionary biology. If you are now going to be able to drop the notion of a sharp dividing line; a single factor; a one generation step in which the speciation suddenly occurs, then you will have made enormous strides in elementary comprehension -- an essential first step required before a coherent critique can even be expressed.

Cheers -- sylas

*Note that a single generation event can isolate one individual. Not a whole population. This is the basis of some kinds speciation in plants. For example, by polyploidy (doubling of the chromosome number in one generation) as can occur with plants; though not to my knowledge with animals. (If anyone knows an example, however, let me know!)

You may remember that Professor Smithers Bones (in the guise of Astronaut) visited the Planet Xu and met the inhabitants.
He returned some years later and saw that things had changed. He reported the changes to NASA Man.

NASA Man has a choice.
1. He can asccept an explanation of changes that says essentially 'We can't analyse what went on in the interim years - all we can see is the end result of many changes.' or
2. He can investigate what exactly changed day by day on Planet Xu.

NASA Man realises that for there to be overall changes then there must have been changes on a day by day basis.

NASA Man understands that this will upset people who have it 'all worked out'. Why investigate when there's already a good story that people seem to like?

NASA Man is hardly going to warm to an account of changes that is based on a premise that 'We can't investigate day by day changes' and 'It doesn't happen that way'.

As far as Eric's model goes I have no doubt it reflects the thinking of evolutionists. I have no doubt that they have written a myriad of papers telling us all 'How it happens by accumulated differences.' I also don't doubt that if you want a career in Biology you have to tow that line.

I don't accept the 'accumulated differences version.' I think it's sloppy, untestable and leads to contradictory results. I can show that. I have explained why. I am happy to explain why again.

But if my arguments are rebutted on the basis that 'You don't understand' then I'm hardly going to teach you anything.

Magellan

[ericmurphy]

*Note that a single generation event can isolate one individual. Not a whole population. This is the basis of some kinds speciation in plants. For example, by polyploidy (doubling of the chromosome number in one generation) as can occur with plants; though not to my knowledge with animals. (If anyone knows an example, however, let me know!)


Tetraploid frogs. (http://onlinelibrary.wiley.com/doi/10.1002/jez.1401410306/abstract)

[ericmurphy]

<pointless babbling snipped>

As far as Eric's model goes I have no doubt it reflects the thinking of evolutionists. I have no doubt that they have written a myriad of papers telling us all 'How it happens by accumulated differences.' I also don't doubt that if you want a career in Biology you have to tow that line.

Magellan, it's not a matter of "toeing the line." It's a matter of being able to think things through on your own, evaluating arguments, weighing evidence, and assessing credibility. But in order to do that, you need to be able to understand what is being discussed in the first place.

I didn't copy my model down from some website (as you—poorly—attempted to do with your "beetles," mistakenly using an illustration of natural selection to try to illustrate speciation). I have in my head a reasonably well-thought-out model of how speciation could potentially occur. I can think through the implications of that model, imagine what has to be true in order for it to be correct, and evaluate it against the background knowledge I possess about the world around me.

You can do none of those things. You don't have sufficient background knowledge even to comprehend my model, let alone try to evaluate it against observation.


I don't accept the 'accumulated differences version.'

We know you don't. We also know you have been unable to articulate a reason why you don't accept it. You cannot explain why you think it is somehow more likely that two gene pools, isolated from each other, will somehow stay in synchronization when there are infinitely many ways how they could be different, and only one way they can be the same.


I think it's sloppy, untestable and leads to contradictory results. I can show that. I have explained why. I am happy to explain why again.

You can't "show" it. You never explained it in the first place, so you certainly won't be able to do it "again." And just using a letter as a symbol to stand for something doesn't magically turn a statement into "mathematics."


But if my arguments are rebutted on the basis that 'You don't understand' then I'm hardly going to teach you anything.

You're not going to teach us anything because you don't know anything to teach.

[sylas]

As far as Eric's model goes I have no doubt it reflects the thinking of evolutionists. I have no doubt that they have written a myriad of papers telling us all 'How it happens by accumulated differences.' I also don't doubt that if you want a career in Biology you have to tow that line.

I don't accept the 'accumulated differences version.' I think it's sloppy, untestable and leads to contradictory results. I can show that. I have explained why. I am happy to explain why again.


Not accepting the model is your prerogative; of course. Coherent criticisms still need to be of the actual model proposed by evolutionists and not some variant you propose yourself. Analogies are not criticisms, for example.

I have not yet seen any criticism of the model that really does use the model. Being able to describe the model yourself is, of course, a basic requirement for being able to say what is wrong with it. So far all I have seen is failures to understand the model; anything approaching criticism has either been trivially incorrect, or else founded on some different model which is indeed incorrect and therefore not used in biology.

Comments such as the remark about having got rid of genetic events continue to reinforce the impression that you still don't understand the model you purport to have criticized. I admit to not taking you very seriously, because I still think much of your contributions are deliberate games to muddy the water. But I'm always ready to revise that impression if and when we start to get comments actually using the evolutionary model to propose possible things wrong with it.

By the way, this is what I did for Eric's first account of the model. That allowed the issue to be fixed.

I am, by the way, thinking of producing a simple simulation that can be a basis for discussion; if I get around to it, it will be a new thread.

All the various aspects of Eric's model that can be seen over a short time span are directly observed and tested. The accumulation of changes is an observation; not an assumption. Reduced fertility across subspecies or outbreeding depression is an observation. The grey areas where it is not clear whether or not two groups correspond to two species are an observation.

Cheers -- sylas

[rogue06]

*Note that a single generation event can isolate one individual. Not a whole population. This is the basis of some kinds speciation in plants. For example, by polyploidy (doubling of the chromosome number in one generation) as can occur with plants; though not to my knowledge with animals. (If anyone knows an example, however, let me know!)

According to Wiki "Polyploidy occurs in some animals, such as goldfish, salmon, and salamanders" and cites this paper (http://www.springerlink.com/content/n3rr5m124g728271/) as an example. I had several more examples on my recently stolen computer.

[sylas]

Tetraploid frogs. (http://onlinelibrary.wiley.com/doi/10.1002/jez.1401410306/abstract)

Thank you... and also thanks rogero.

Eric's paper is from 1959, about the occurrence of polyploidy in frogs. I'm behind the times. Using this I googled further for examples of speciation by polyploidy and found this:
Ptacek, M.B. et. al. (1994) Speciation by Polyploidy in Treefrogs: Multiple Origins of the Tetraploid, Hyla versicolor (http://www.jstor.org/pss/2410495) in Evolution 48(3) pp. 898-908

Ta muchly everyone! -- sylas

[magellan004]

For some unfathomable reason Magellan thinks Faid thinks I grew up in the Outback. Can you give us some insight into why you would think that, Magellan? Maybe you think Faid thinks you were saying I grew up around Aborigines and hence would have to be isolated from them before I could magically have a child who couldn't interbreed with Aborigines?

Is that what you "think," Magellan? If "thinking" isn't too grand a term for what happens between your ears?

It's actually a crucial point that Faid grappled with and failed to come to terms with.

Evolution requires that -
A person who's family and ancestors all lived in (say) America and who was well able to breed with Aborigines (even though that person nor that person's family ever had contact with Aboringines ) one day gives birth to a child that has the same interbreeding capacity as the parents except for one differencwe - the child cannot breed with Aborigines.

Let us not permit Faid's struggle to distract us from this central truth.

Magelan

[magellan004]

Comments such as the remark about having got rid of genetic events continue to reinforce the impression that you still don't understand the model you purport to have criticized. I admit to not taking you very seriously, because I still think much of your contributions are deliberate games to muddy the water. But I'm always ready to revise that impression if and when we start to get comments actually using the evolutionary model to propose possible things wrong with it.


The 'genetic events' thingamy was 'a thing wrong with it'. I pointed that out to Eric a few days ago.

Eric likes a little bit of sugar with his medicine.

Magellan

[sylas]

The 'genetic events' thingamy was 'a thing wrong with it'. I pointed that out to Eric a few days ago.

I don't believe you. I don't think Eric ever had that particular error in his model before msg #1196; and he corrected it immediately that the problem was pointed out.

The corrected account is in msg #1207, and it still includes genetic events in the same place that they have been throughout the thread. No-one has ever shown any problem with having genetic events as one of the aspects of the speciation model. Genetic events -- mutations -- are observed. The accumulation of difference over time is observed. The role of genetic differences in reduced fertility is observed.

What is yet to be observed, by me at least, is a case where you've actually managed to describe and use the model you purport to criticise. The thing to do would give an explicit message number if you want me to consider a post where you think you've ever done anything like this.

Cheers -- sylas
Eric likes a little bit of sugar with his medicine.

Magellan[/QUOTE]

[ericmurphy]

It's actually a crucial point that Faid grappled with and failed to come to terms with.

That you think it's a "crucial point" just illustrates how utterly, hopelessly lost you are, Magellan. That you seem to think humans (or any other species) could speciate in a single generation is exactly what everyone has been hammering you on for weeks now.


Evolution requires that -
A person who's family and ancestors all lived in (say) America and who was well able to breed with Aborigines (even though that person nor that person's family ever had contact with Aboringines ) one day gives birth to a child that has the same interbreeding capacity as the parents except for one differencwe - the child cannot breed with Aborigines.

Evolution "requires" no such thing. That you seem to think evolutionary theory "requires" that humans (or any other species) speciate in a single generation is exactly what everyone has been hammering you on for weeks now.

Seriously, Magellan: you have a kindergartner's understanding of evolutionary theory.


Let us not permit Faid's struggle to distract us from this central truth.

The only one "struggling" here is you, Magellan. You're like a squirrel trying to discuss aerodynamic engineering.

[ericmurphy]

The 'genetic events' thingamy was 'a thing wrong with it'. I pointed that out to Eric a few days ago.

It wasn't a "wrong thing with it." It simply was inapplicable to my particular model. As the several papers linked to just in the past few posts point out, polyploidy can be the beginnings of reproductive isolation eventually resulting in speciation.


Eric likes a little bit of sugar with his medicine.

The notion that you are handing out any "medicine," when in fact you're getting dealt repeated amputations, is pretty laughable.

[ericmurphy]

I don't believe you. I don't think Eric ever had that particular error in his model before msg #1196; and he corrected it immediately that the problem was pointed out.

He didn't "correct" me; he pointed out that it's unnecessary to my model. Which, of course, it's not.

ETA: Also, Magellan is implying, incorrectly, that "genetic events" have no place in my model. That is of course false. "Genetic events" have a central place in my model; they're simply not used as a method creating initial reproductive isolation between the two subpopulations.

[Tiggy]

Wow Clownshoes, you've managed to nurse this thing to 80+ pages and 1200+ posts.

That's some world class attention whoring! :thumb:

- T

[magellan004]

Evolution "requires" no such thing. That you seem to think evolutionary theory "requires" that humans (or any other species) speciate in a single generation is exactly what everyone has been hammering you on for weeks now.

I've shown why twice now. This will be the third time. Please take notes with pen and paper. Your memory can't be relied upon.

This is the only way Speciation can occur-



1. In Year 0 there is a tribe of Aborigines in Africa.
2. In Year 2 the tribe is split into two - Group A heads off for Australia and stays unchanged in terms of interbreeding ability for 50,000 years.
3. In Year 2 Group B heads for America.

...

10. In Year 50,000 none of group B can interbreed with Group A.

How could that happen? We need to examine the intervening years.
4. In Year 4 all Group B members can interbreed with group A.
...
9. In Year 49,999 no Group B members can interbreed with group A.


5. In Year 29,999 all Group B members can interbreed with group A.
...
8. In Year 49,998 no Group B members can interbreed with group A.

Therefore -
6. In Year 30,000 one Group B member cannot interbreed with group A.
...
7. In Year 40,000 some Group B members cannot interbreed with group A.

Let's call the first individual to be unable to breed with Group A (in Year 30,000 ) 'Factor X type person'. That child's parents are 'Non-X type people'.
'Factor X type People' are Group B individuals that cannot interbreed with Group A.
'Non-X type people ' are Group B individuals that can breed with group A.

We know that 'Factor X type People' are the only survivors in Group B in Year 50,000.
That means -
1. Something wiped out 'Non- X type People' and
2. 'Factor X type People' cannot have 'Non- X type People' as children even though ''Factor X type People' can breed with 'Non-X type People'.

Therefore whatever wiped out 'Non-X type People' did not wipe out 'Factor X type People' because of one reason - Factor X.

Therefore having Factor X means -
1. You cannot breed with Group A.
2. You are immune to whatever wiped out your parent type.
3. You cannot have 'Non-X type People' as children,

One interbreeding difference results in three effects.

Now I do request that in place of the usual denials and table-thumping, you show any errors in my reasoning.

Magellan

[sylas]

I've shown why twice now. This will be the third time. Please take notes with pen and paper. Your memory can't be relied upon.

This is the only way Speciation can occur-



1. In Year 0 there is a tribe of Aborigines in Africa.
2. In Year 2 the tribe is split into two - Group A heads off for Australia and stays unchanged in terms of interbreeding ability for 50,000 years.
3. In Year 2 Group B heads for America.

...

10. In Year 50,000 none of group B can interbreed with Group A.

How could that happen? We need to examine the intervening years.
4. In Year 4 all Group B members can interbreed with group A.
...
9. In Year 49,999 no Group B members can interbreed with group A.


5. In Year 29,999 all Group B members can interbreed with group A.
...
8. In Year 49,998 no Group B members can interbreed with group A.

Therefore -
6. In Year 30,000 one Group B member cannot interbreed with group A.
...
7. In Year 40,000 some Group B members cannot interbreed with group A.

Let's call the first individual to be unable to breed with Group A (in Year 30,000 ) 'Factor X type person'. That child's parents are 'Non-X type people'.
'Factor X type People' are Group B individuals that cannot interbreed with Group A.
'Non-X type people ' are Group B individuals that can breed with group A.

We know that 'Factor X type People' are the only survivors in Group B in Year 50,000.
That means -
1. Something wiped out 'Non- X type People' and
2. 'Factor X type People' cannot have 'Non- X type People' as children even though ''Factor X type People' can breed with 'Non-X type People'.

Therefore whatever wiped out 'Non-X type People' did not wipe out 'Factor X type People' because of one reason - Factor X.

Therefore having Factor X means -
1. You cannot breed with Group A.
2. You are immune to whatever wiped out your parent type.
3. You cannot have 'Non-X type People' as children,

One interbreeding difference results in three effects.

Now I do request that in place of the usual denials and table-thumping, you show any errors in my reasoning.

Magellan

Here are some of the errors.

1. Treating the capacity to breed as a binary yes no proposition.

The biological reality is that for two individuals, fertility ranges over a continuum, from totally infertile, to weakly fertile, to strongly fertile.

We know this already simply from the human experience. Some couples are infertile; and unable to have children. Some couples have children easily. Some couples find it very hard, but not impossible to have children. They need to try repeatedly to achieve pregnancy, or else take unusually special care during pregnancy to bring a baby to term.

In a computer model, or in descriptions of field work in biology, fertility for a couple is typically represented as the probability of having children when they mate; or else as the expected number of children that will result in cases where organisms can have large numbers of offspring from mating.

2. The above account speaks of fertility with a group, rather than with an individual, as being a binary quality

Even in a highly simplified model where couples are either fertile or not fertile; you still do not have have a clear division between "can breed with group A", and "cannot breed with group A". For any given individual, you will have a certain number of potential mates in group A. This will vary from zero (total infertility of an individual with all of group A) to full fertility (an individual is able to mate with any of the group A individuals). The account above ignores the case where an individual is able to mate with some partners in group A, but not with others.

3. Speaking of a single factor X as determining fertility

We already know that in reality, there are many factors which are required for fertility. A couple must be able to have all the following:

Successful fertilization of sperm and egg.
Successful implantation of the zygote.
Successful development of the embryo.
Successful maintenance of the embryo in utero until birth.
Birth of a child able to live to adulthood.
An adult at the end who is able to have children.


This is an incomplete list. Disruption of any one of these will introduce infertility. There is no single factor associated with an individual that can be used to compare with that factor in another individual to determine whether that couple can breed successfully.


* * * * *

Here is an extract from Magellan's post showing clearly how the errors arise.


Let's call the first individual to be unable to breed with Group A (in Year 30,000 ) 'Factor X type person'. That child's parents are 'Non-X type people'.
'Factor X type People' are Group B individuals that cannot interbreed with Group A.
'Non-X type people ' are Group B individuals that can breed with group A.

This is an example of using "ability to breed with group A" as a binary quality.

In reality, evolutionary models will involve an intermediate stage of incomplete isolation, in which there are differing numbers of potential partners in group A.

In the initial stage, individuals have the same number of potential partners in group A and in group B.

In the final stage of complete isolation, no individual in group A has any potential partners in group B, and conversely.

In the intermediate stages, you don't have some individuals who have full fertility with A and others who have none. You have a slowly decreasing number of potentially fertile PAIRS, with one partner from A and one from B. When this reaches zero, you have complete isolation and speciation by the model.


* * * *

This is again a case where Magellan has simply not described the evolutionary model accurately. Until that is achieved, the criticisms will miss the point.

All the above errors in Magellan's descriptions of the evolutionary model have been pointed out, many times, previously in the thread.

These are elementary errors of comprehension. It has nothing to do with whether the evolutionary model is a good match with reality or not; the fundamental problem is that Magellan is still unable to describe the model accurately that he purports to criticize.

For anyone who is actually serious about looking at the model in full precision, I do plan to write and put up a simple computer simulation that encodes the model. Given the simulation, it will be easy to give very precise definitions and encode them as functions. It will be easy to produce a trace of all the generations and see what differences actually arise.

It will also allow me to be fully precise about what I mean about there being no one factor X. The model of genetic distance I am using to represent outbreeding depression is that of Euclidean distance, and it is trivially impossible to give a single number or factor X that represents which part of the genome determines fertility with another individual. Fertility in this simple model is a property of the entire genome of the two individuals being tested for fertility, and the entire genome for both individuals in a couple in order to determine fertility of that couple. It is mathematically impossible to give any more simple abstraction for the individual that would allow fertility to be tested with other individuals.

Assuming I get this done, it will be in a new thread.

Cheers -- sylas

[Faid]

Yes, almost -

It seems that Faid thinks what I was saying was -

(For example) Eric grew up around Aborigines and got isolated from them before Eric magically had a child who couldn't interbreed with Aborigines.

You and I know that no one in their right mind could arrive at that from what I said. Unfortunately he won't listen to either of us.

MagellanOh I would be immensely happy to listen to you, if you could actually explain what you meant by

"It's like Eric (example) who has never had contact with Aborigines, one day having a child that cannot breed with aborigines"

Can you?

[Faid]

It's actually a crucial point that Faid grappled with and failed to come to terms with.

Evolution requires that -
A person who's family and ancestors all lived in (say) America and who was well able to breed with Aborigines (even though that person nor that person's family ever had contact with Aboringines ) one day gives birth to a child that has the same interbreeding capacity as the parents except for one differencwe - the child cannot breed with Aborigines.

Let us not permit Faid's struggle to distract us from this central truth.

MagelanAbsolute hogwash. I addressed all that nonsense many pages ago (http://www.theologyweb.com/campus/showthread.php?144614-Evolution-of-The-Beetles&p=3193017#post3193017), in a post whose main points you failed to refute or even aknowledge.

If, in your hypothetical model, Eric were to have a child for which it would be impossible to breed with "aborigines" or whatever other group, then it should be almost impossible for Eric himself to do so in the first place. We would have to go back a long time in the past, to find one of Eric's ancestors for whom it would only be very very very hard to breed with member of that group. And further back until we find an ancestor that could only very hardly interbreed, and so on. Assuming we have a continuous reproductive barrier in effect between Eric's group and the other group, of course.

Why do you keep pretending that your various inanities have not been addressed? Is it because you've run out of original ones, and have to regurgitate the old ones again and again?

[Faid]

And Mags, don't think for a moment I forgot that latest howler of yours:
Here's a question even a child could answer:

Suppose we call Factor X "difference of A+B+C+D+E+F". You have already agreed we can do that.

Now, imagine we have two organisms that differ in A, B, C, D, E and F.

Which of the two organisms has "factor X"?

Straight answer, please.


The different one.

Magellan

So Mags: If A is different than B in some way, how exactly is B not different from A in the same way?

[magellan004]

This is a response to Sylas’s Post 1231.

First of all let me thank you for at last posting a response that does not contain insults. You did include one sneaky little innuendo but overall your post is about ideas, not personalities. Welcome to the discussion.

Here are some of the errors.

1. Treating the capacity to breed as a binary yes no proposition.

The biological reality is that for two individuals, fertility ranges over a continuum, from totally infertile, to weakly fertile, to strongly fertile.

We know this already simply from the human experience. Some couples are infertile; and unable to have children. Some couples have children easily. Some couples find it very hard, but not impossible to have children. They need to try repeatedly to achieve pregnancy, or else take unusually special care during pregnancy to bring a baby to term.

In a computer model, or in descriptions of field work in biology, fertility for a couple is typically represented as the probability of having children when they mate; or else as the expected number of children that will result in cases where organisms can have large numbers of offspring from mating.

Let’s get our terms straight for a start. Speciation involves ‘An ability or capacity to interbreed.’ So if we clear up your confusing terminology we get –

‘The biological reality is that for two individuals, the capacity to interbreed ranges over a continuum, from totally capacity to interbreed , to weakly able to interbreed, to strongly able to interbreed.


We know this already simply from the human experience. Some couples have no ability to interbreed ; and unable to have children. Some couples have children easily. Some couples find it very hard, but not impossible to have children. They need to try repeatedly to achieve pregnancy, or else take unusually special care during pregnancy to bring a baby to term.

If some individuals have no ability to interbreed then those individuals do not belong to a Species – a group where members have an ability to interbreed.

Eric and I are not talking about (your phrase ) ‘fertility’. Evolution is not talking about your ‘fertility’. A sterile female is a member of a group where each member has an ability to interbreed. .Eric and I are talking about ‘Does this individual have the capacity to interbreed with that individual?’ Another way to put that is ‘Do members of Group B have the ability to interbreed with members of Group A?’

Let’s take the case where there is no ‘Yes/No’ answer .

‘Do these Chimps have the ability to interbreed with humans?’
Answer ‘There can be no ‘Yes/No’ answer. It is not a binary proposition. Some Chimps and Humans could interbreed.’
If that is the case then ‘Humans are a separate species to chimps because they cannot interbreed’ is invalid.
If we cannot have a Yes/No test for ‘Members of this group do not have the ability to interbreed with members of that group’ then ‘The ability of individuals from one group to interbreed with members of another group’ cannot be used as a criteria of Speciation. There will never be any group that meets the ‘These cannot interbreed with those ‘ criterion.

If you wish to introduce a definition of Species that deals with levels of fertility then please do so. That will mean that ‘Ability to interbreed’ is jettisoned. What I mean by that is if you wish to say that ‘ ‘Can Humans interbreed with Chimps?’ is not a binary proposition’ then we need a new definition of Species – which in the discussion I have had with Eric means – ‘Can this group interbreed with that group? Answer = Yes or No.’



2. The above account speaks of fertility with a group, rather than with an individual, as being a binary quality

Even in a highly simplified model where couples are either fertile or not fertile; you still do not have have a clear division between "can breed with group A", and "cannot breed with group A". For any given individual, you will have a certain number of potential mates in group A. This will vary from zero (total infertility of an individual with all of group A) to full fertility (an individual is able to mate with any of the group A individuals). The account above ignores the case where an individual is able to mate with some partners in group A, but not with others.
Nothing happens on a group level. "can breed with group A" has, as far as I am concerned always meant ‘can breed with any member of Group A.’ (How could it mean anything different?) If a Group B member can breed with at least one Group A member then Group A and Group B cannot be separate species. It is a binary proposition. ‘Is this group a different species to that group?’



3. Speaking of a single factor X as determining fertility

We already know that in reality, there are many factors which are required for fertility. A couple must be able to have all the following:

Successful fertilization of sperm and egg.
Successful implantation of the zygote.
Successful development of the embryo.
Successful maintenance of the embryo in utero until birth.
Birth of a child able to live to adulthood.
An adult at the end who is able to have children.


This is an incomplete list. Disruption of any one of these will introduce infertility. There is no single factor associated with an individual that can be used to compare with that factor in another individual to determine whether that couple can breed successfully.
Any one factor will introduce inability to interbreed. There is no single factor.
But you are saying that any one of these factors will introduce an inability to interbreed. All we need is one factor – Factor X.
Let’s say that two parents in Group B that can interbreed with members in Group A have a child which has NOT this attribute ‘Successful fertilization of sperm and egg.’ That will be Factor X – it renders the child unable to interbreed with members of Group A. We don’t need any other factor. The child has one factor that renders it different to it’s parents. Call that factor ‘Factor X’.

That begs the question of how that child can have any offspring at all. And that’s why the ‘Inability to interbreed’ test is so far removed from reality to be fantasy. But if you or Eric or evolutionists want to argue that ‘Inability to interbreed ‘ is a measurable feature then you have to stick with that paradox.


In reality, evolutionary models will involve an intermediate stage of incomplete isolation, in which there are differing numbers of potential partners in group A.

In the initial stage, individuals have the same number of potential partners in group A and in group B.

In the final stage of complete isolation, no individual in group A has any potential partners in group B, and conversely.

In the intermediate stages, you don't have some individuals who have full fertility with A and others who have none. You have a slowly decreasing number of potentially fertile PAIRS, with one partner from A and one from B. When this reaches zero, you have complete isolation and speciation by the model.
Let’s clean your post up –

‘In the intermediate stages, you don't have some individuals from Group B who have an ability to interbreed with members of Group A. ‘
You must. I have shown why. If at Stage A every member of Group B can interbreed with every member of Group A and at a later stage - Stage B every member of Group B is unable to interbreed with any member of Group A then you do have some individuals from Group B who, in the intermediate stages , can interbreed with members of Group A and you do have some individuals from Group B who cannot interbreed with members of Group A.

I look forward to you providing a model where ‘Ability to interbreed ‘ is not a feature that has to start with one individual.


Magellan

[magellan004]

Oh I would be immensely happy to listen to you, if you could actually explain what you meant by

"It's like Eric (example) who has never had contact with Aborigines, one day having a child that cannot breed with aborigines"

Can you?

I gathered you were questioning this -

The only way we can end up with all members of Group B being unable to interbreed with any Group A members is to have a child born in Group B that is the first member of Group B unable to breed with any member of Group A.

As an example - The only way we could end up with Eric's child unable to interbreed with an Aborigine is for Eric to have a child with Factor X - An inability to breed with Aborigines.

Magellan

[magellan004]

Absolute hogwash. I addressed all that nonsense many pages ago (http://www.theologyweb.com/campus/showthread.php?144614-Evolution-of-The-Beetles&p=3193017#post3193017), in a post whose main points you failed to refute or even aknowledge.

If, in your hypothetical model, Eric were to have a child for which it would be impossible to breed with "aborigines" or whatever other group, then it should be almost impossible for Eric himself to do so in the first place. We would have to go back a long time in the past, to find one of Eric's ancestors for whom it would only be very very very hard to breed with member of that group. And further back until we find an ancestor that could only very hardly interbreed, and so on. Assuming we have a continuous reproductive barrier in effect between Eric's group and the other group, of course.

Why do you keep pretending that your various inanities have not been addressed? Is it because you've run out of original ones, and have to regurgitate the old ones again and again?

That would be true if the meaning of Species were 'It's very, very hard for Humans to breed with Chimps.'

Magellan

[magellan004]

And Mags, don't think for a moment I forgot that latest howler of yours:



So Mags: If A is different than B in some way, how exactly is B not different from A in the same way?

The difference is Factor X.
If members of Group A in Year 100,000 are the same as members of Group A in Year 1 and Members of Group B differ to members of Group A , then the difference is Factor X.

Magellan

[sylas]

Magellan, I still do not think you are entirely serious; I think you are mostly just trolling. If I am wrong about that, and doing you an injustice, so be it. If you are actually genuine, I do not think I have the capacity to explain any better than I have done already in the previous post; so it doesn't matter.

My previous post stands, unmodified, and if there is anyone other than you who finds it even remotely confusing or incorrect, I'll sit up and take notice.

In the meantime, I am more interested in getting a concrete example of Eric's model, as Eric presents it, in the form of a computer simulation. Whether you think the model is a good reflection of biology or not, a simulation will show that the model is internally consistent, and that speciation in the model is defined in terms of fertility as a binary relation between individuals.

You'll be welcome to contribute in the thread I start on example simulations, if you like.

Be that as it may, I will comment briefly on a few points.




‘Do these Chimps have the ability to interbreed with humans?’
Answer ‘There can be no ‘Yes/No’ answer. It is not a binary proposition. Some Chimps and Humans could interbreed.’
If that is the case then ‘Humans are a separate species to chimps because they cannot interbreed’ is invalid.


No human can interbreed with any chimp; therefore they are different species by Eric's definition.

What Eric's model means is that at some point in the past, there were two populations, one of which was ancestral to modern chimpanzees, and one of which was ancestral to modern humans, and that there was a partial level of fertility between those two groups.

Call the groups, proto-humans, and proto-chimpanzees. It is an implication of the model that at some point in the past, there was a time when SOME proto-chimpanzees had the capacity to breed with SOME proto-humans, and hence at this time speciation was not complete. At that time, you only had incipient species -- a phenomenon which is observed today in some species that are (evidence suggests) in the process of splitting into two species.



If we cannot have a Yes/No test for ‘Members of this group do not have the ability to interbreed with members of that group’ then ‘The ability of individuals from one group to interbreed with members of another group’ cannot be used as a criteria of Speciation. There will never be any group that meets the ‘These cannot interbreed with those ‘ criterion.


You most certainly can have tests which return a clear yes in one case (humans and chimpanzees for example, are unambiguously different species) and a clear no in another case (Europeans and Chinese are unambiguously the same species), but which are unclear or uncertain in intermediate cases. Orcas might be one species, or perhaps about three species, and it's hard to tell.



Any one factor will introduce inability to interbreed. There is no single factor.
But you are saying that any one of these factors will introduce an inability to interbreed. All we need is one factor – Factor X.
Let’s say that two parents in Group B that can interbreed with members in Group A have a child which has NOT this attribute ‘Successful fertilization of sperm and egg.’ That will be Factor X – it renders the child unable to interbreed with members of Group A. We don’t need any other factor. The child has one factor that renders it different to it’s parents. Call that factor ‘Factor X’.


You can certainly postulate YOUR model in which there is one factor that matters. It's not an implication of Eric's model, and definitely not a part of the models used in biology. It's not accurate as a description of what we observe.

The point is this. By insisting on having just one factor that can be tested and resolve the question of whether or not two individual are fertile with each other, you are -- again -- proposing your own personal addition to the model. It's not a part of Eric's model. It's not an implication of Eric's model. It's not a part of biological models.

If you want to give a sensible critique of the evolutionary models or Eric's model (which IS a perfectly good description of one of the most important models of speciation in biology), then you have to base that critique on the evolution model.

I have a concrete critique of your "single factor" suggestion resolving fertility. The problem is that a single factor would mean genetic drift moves species towards a capacity for interbreeding almost as often as it causes them to diverge. The evidence falsifies this.

Hence a simulation using a single factor will fail as a good model of biology precisely because of the fact only one factor is used in the model.

Just to cross the ts and dot the is... by single factor I mean something representable as a single number. A multi-dimensional factor, being a vector, or a list of sub-factors, for example, is not a "single factor". A sum of numbers is on the other hand a single factor; and will fail as an adequate representation of biology for speciation simulations.

Some of these issues will be more clear -- or at least harder to spin into mangled distortions -- when encoded as a concrete computer simulation. I have cited a paper previously which does this, and quoted their model of fertility -- it absolutely cannot be reduced to a quality of some single factor.

But I don't have the code for the simulation -- only the description, and we've seen how well descriptions get comprehended. So I am writing my own simulation, and will put it up for others to judge on its own merits, in a new thread.

Cheers -- sylas

[magellan004]

My previous post stands, unmodified, and if there is anyone other than you who finds it even remotely confusing or incorrect, I'll sit up and take notice.
You write posts directed at me telling me that you are uninterested in my response.

See a shrink for that.

Magellan

[ericmurphy]

I've shown why twice now. This will be the third time. Please take notes with pen and paper. Your memory can't be relied upon.

You were wrong the first two times, and you'll be wrong this time. And the time after that. And the time after that. And every time you raise this bogus "argument."


This is the only way Speciation can occur-



1. In Year 0 there is a tribe of Aborigines in Africa.
2. In Year 2 the tribe is split into two - Group A heads off for Australia and stays unchanged in terms of interbreeding ability for 50,000 years.
3. In Year 2 Group B heads for America.

...

10. In Year 50,000 none of group B can interbreed with Group A.

How could that happen? We need to examine the intervening years.
4. In Year 4 all Group B members can interbreed with group A.
...
9. In Year 49,999 no Group B members can interbreed with group A.


5. In Year 29,999 all Group B members can interbreed with group A.
...
8. In Year 49,998 no Group B members can interbreed with group A.

Therefore -
6. In Year 30,000 one Group B member cannot interbreed with group A.
...
7. In Year 40,000 some Group B members cannot interbreed with group A.

You still think it all has to happen in a single generation. How many times do we have to tell you this?

http://www.planet-deepblu.com/~eric/graphic_links/InterfertilityVsDifferences.png

It doesn't "have to happen" that way under evolutionary theory.

LEARN MY MODEL. Stop making criticisms of your OWN wrong notions of how you think the model works, and address my actual model.



Let's call the first individual to be unable to breed with Group A (in Year 30,000 ) 'Factor X type person'. That child's parents are 'Non-X type people'.
'Factor X type People' are Group B individuals that cannot interbreed with Group A.
'Non-X type people ' are Group B individuals that can breed with group A.

We know that 'Factor X type People' are the only survivors in Group B in Year 50,000.
That means -
1. Something wiped out 'Non- X type People' and
2. 'Factor X type People' cannot have 'Non- X type People' as children even though ''Factor X type People' can breed with 'Non-X type People'.

Therefore whatever wiped out 'Non-X type People' did not wipe out 'Factor X type People' because of one reason - Factor X.

We've corrected you innumerable times on this idiot notion that a single "factor X" results in an inability to interbreed. Look at this diagram again:

http://www.planet-deepblu.com/~eric/graphic_links/InterfertilityVsDifferences.png

You can disagree that this is the case if you want. But it's part and parcel of my model. If you want to address my model, then you HAVE TO ADDRESS MY MODEL. You can't keep changing things around about my model and then criticizing it as if it had those changes.

It doesn't.


Therefore having Factor X means -
1. You cannot breed with Group A.
2. You are immune to whatever wiped out your parent type.
3. You cannot have 'Non-X type People' as children,

One interbreeding difference results in three effects.

Now I do request that in place of the usual denials and table-thumping, you show any errors in my reasoning.

Magellan

The "errors in your reasoning" are that you are not addressing my model. You are making up your OWN model, which CANNOT produce speciation, and then criticizing THAT model.

I don't CARE if your model can't lead to speciation.

[ericmurphy]

Let’s get our terms straight for a start. Speciation involves ‘An ability or capacity to interbreed.’ So if we clear up your confusing terminology we get –
Why are you the only one who is ever confused by "terminology," Magellan? Sylas's post is perfectly clear and straightforward. Has it ever occurred to you that it is your own ignorance that makes other peoples terminology "confusing"?




‘The biological reality is that for two individuals, the capacity to interbreed ranges over a continuum, from totally capacity to interbreed , to weakly able to interbreed, to strongly able to interbreed.


Replacing "fertility" with "ability to interbreed" does exactly nothing for clarity, Magellan. You have this idea that replacing words with the definitions of those words does something other than make sentences longer.


If some individuals have no ability to interbreed then those individuals do not belong to a Species – a group where members have an ability to interbreed.

So you really do think that a woman who is sterile—say, due to a tubal ligation—is no longer human, then?


Eric and I are not talking about (your phrase ) ‘fertility’.
I don't know what you're talking about, Magellan, but I definitely am talking about fertility. Given your incomprehension of the majority of what I say, please don't presume to speak for me with respect to what I'm talking about.


Evolution is not talking about your ‘fertility’.

Evolutionary theory most certainly is talking about fertility. Fertility, or lack thereof, is a central element of evolutionary theory.

You should also refrain from talking about what evolutionary theory is talking about, since you have essentially no understanding of what evolutionary theory says.


A sterile female is a member of a group where each member has an ability to interbreed. .Eric and I are talking about ‘Does this individual have the capacity to interbreed with that individual?’ Another way to put that is ‘Do members of Group B have the ability to interbreed with members of Group A?’

That might be what you're talking about, but it most certainly is not what I am talking about. I am presenting a model of how speciation happens, and am trying, unsuccessfully, to get you to understand that model so that you can critique it. Instead, you keep criticizing some other model of speciation that has little to do with my model.


Let’s take the case where there is no ‘Yes/No’ answer .

‘Do these Chimps have the ability to interbreed with humans?’
Answer ‘There can be no ‘Yes/No’ answer. It is not a binary proposition. Some Chimps and Humans could interbreed.’
If that is the case then ‘Humans are a separate species to chimps because they cannot interbreed’ is invalid.

How can you be this clueless, Magellan? Just because interfertility can take a range of values from 100% to zero does not mean it can never be zero!


If we cannot have a Yes/No test for ‘Members of this group do not have the ability to interbreed with members of that group’ then ‘The ability of individuals from one group to interbreed with members of another group’ cannot be used as a criteria of Speciation. There will never be any group that meets the ‘These cannot interbreed with those ‘ criterion.

There are three possible answers to the question, can these two organisms interbreed: "yes," "possibly," and "no." That doesn't mean the answer can never be "yes" or "no."


If you wish to introduce a definition of Species that deals with levels of fertility then please do so. That will mean that ‘Ability to interbreed’ is jettisoned. What I mean by that is if you wish to say that ‘ ‘Can Humans interbreed with Chimps?’ is not a binary proposition’ then we need a new definition of Species – which in the discussion I have had with Eric means – ‘Can this group interbreed with that group? Answer = Yes or No.’

Once more, the same problem:

http://www.planet-deepblu.com/~eric/graphic_links/GrayVsBandW.png

Here's the question:

Can most of this population breed with this other population?

Possible answers:


Yes, nearly all of them can, and therefore both populations are the same species.
Some of them can but many of them cannot; therefore they appear to be two populations which were originally the same species, but now appear to be undergoing a process of speciation.
No, none of them can; they are definitely different species.


Apparently, Magellan cannot imagine that 2. is a possible answer to the question.



Nothing happens on a group level.
Speciation does. Speciation only happens at the group level.


"can breed with group A" has, as far as I am concerned always meant ‘can breed with any member of Group A.’ (How could it mean anything different?)
See above.


If a Group B member can breed with at least one Group A member then Group A and Group B cannot be separate species. It is a binary proposition. ‘Is this group a different species to that group?’

The same problem:

http://www.planet-deepblu.com/~eric/graphic_links/GrayVsBandW.png



Any one factor will introduce inability to interbreed. There is no single factor.
Well, the second part is right—finally! But the first part isn't. It's definitely not true that, e.g., the gene coding for eye color in humans can produce an inability to interbreed.

But you still have this notion that fertility is either 100% or zero when we keep giving you simple, everyday examples that prove this is not so. Many human beings have fertility that is somewhere between these values. I know of a woman who got pregnant with twins the first time she ever had sex. I know of another woman who tried for four years to get pregnant before finally succeeding. I know of a third woman who was unable to carry a fetus to term even after extensive use of fertility drugs.

Your notion that fertility is always 100% or zero is totally refuted by everyday experience.


But you are saying that any one of these factors will introduce an inability to interbreed. All we need is one factor – Factor X.
Still wrong. If you were correct, we would never see the examples I have provided.


Let’s say that two parents in Group B that can interbreed with members in Group A have a child which has NOT this attribute ‘Successful fertilization of sperm and egg.’ That will be Factor X – it renders the child unable to interbreed with members of Group A. We don’t need any other factor. The child has one factor that renders it different to it’s parents. Call that factor ‘Factor X’.

Then how do you explain differences in fertility that are not total, Magellan? How do you explain the existence of a woman who got pregnant with twins at the age of sixteen the same night she lost her virginity, and another woman who spent her entire early and mid thirties trying to get pregnant?

What is your explanation for that.


That begs the question of how that child can have any offspring at all.

Really? What question do you think it begs, Magellan? You think there's a question as to whether or not organisms can have offspring?


And that’s why the ‘Inability to interbreed’ test is so far removed from reality to be fantasy. But if you or Eric or evolutionists want to argue that ‘Inability to interbreed ‘ is a measurable feature then you have to stick with that paradox.

It is a measurable feature. We can measure fertility rates in populations in the same way we can measure cancer rates in populations. Fertility is an observable, quantifiable attribute. That you think there's no way to tell whether two populations are interfertile, and to what extent, is one of the reasons you simply cannot understand my model


Let’s clean your post up –

‘In the intermediate stages, you don't have some individuals from Group B who have an ability to interbreed with members of Group A. ‘
That's not "cleaning" sylas's post up. That's a complete reversal of what he said. What sylas said is accurate. What you change his statement into is completely and utterly false.


You must. I have shown why.
You haven't "shown why." You've made a claim. The same claim you always make: that fertility is always 100% or zero. It's not. We've given you proof positive that it's not.


If at Stage A every member of Group B can interbreed with every member of Group A and at a later stage - Stage B every member of Group B is unable to interbreed with any member of Group A then you do have some individuals from Group B who, in the intermediate stages , can interbreed with members of Group A and you do have some individuals from Group B who cannot interbreed with members of Group A.

But you also have members of B who can interbreed with some members of A and not other members of A. You have members of B who produce slightly more offspring with other members of B than with members of A. You have members of B who are more likely to produce offspring with a specific member of A than other members of B are.

It's not a simple matter of members of B suddenly being unable to interbreed with A, and no matter how many times you make that claim, it never becomes any less false.


I look forward to you providing a model where ‘Ability to interbreed ‘ is not a feature that has to start with one individual.

I've already given you one:



We start with a single, freely-interbreeding ancestral population X. All members of this population can interbreed with each other.
At some point, some event or process divides X into two freely-interbreeding subpopulations, A and B. At the time of initial separation, all members of A and B are interfertile not only with other members of their own population but also with members of the other population, and would be interfertile with members of X if there still were any.
The isolating event or process could be geographic isolation due to a new mountain range forming, climate change forming a barrier between two regions, migration patterns reducing or eliminating gene flow between remote areas inhabited by the original population, or colonization of an island by either subpopulation.
Over time, genetic differences in both populations accumulate, so that the members of each population become increasingly different from members of the other population (but selective pressures minimize the differences within a population).
As those differences accumulate, interfertility between populations (if there were any interbreeding between them, which there isn't) slowly declines over time. Again, selective pressures keep interfertility within a population from declining.
After sufficient genetic differences have accumulated, interfertility between A and B declines to zero. At this point, we have two separate species which cannot interbreed.
Even if further events allow an overlap of territories between A and B, they will no longer be able to interbreed, and will remain separate species indefinitely.
As time goes on, both A and B may undergo additional speciation events, similar to the above, with both A and B taking the place of X in the sequence of events.

[ericmurphy]

I gathered you were questioning this -

The only way we can end up with all members of Group B being unable to interbreed with any Group A members is to have a child born in Group B that is the first member of Group B unable to breed with any member of Group A.


The question, Magellan, is why you think it matters.

Let's take population X, the ancestral population from which both populations A and B are descended in my model.

There was undoubtedly at least one ancestor of some member of population A which could not interbreed with at least one ancestor of some member of population B long before the population even split into two subpopulations.

Can you tell us why you think it's significant that there must have been some first member of any population which could not interbreed with any or all members of another population? Why is this trivial point important? Why does it matter? Why do you think it presents a problem for any model of speciation?

[ericmurphy]

That would be true if the meaning of Species were 'It's very, very hard for Humans to breed with Chimps.'

Magellan

The same problem as always:

http://www.planet-deepblu.com/~eric/graphic_links/GrayVsBandW.png

How many times must it be pointed out to you, Magellan, that evolutionary theory [i]predicts[/b] that there will be no rigorous, universally-applicable definition of the word "species"?

[ericmurphy]

The difference is Factor X.
If members of Group A in Year 100,000 are the same as members of Group A in Year 1 and Members of Group B differ to members of Group A , then the difference is Factor X.

Magellan

Magellan: what's the difference between a duck?

[ericmurphy]

You write posts directed at me telling me that you are uninterested in my response.

See a shrink for that.

Try comprehending English for a change, Magellan. What sylas is saying is that nothing you said makes him rethink anything in his post. He's not saying he's not interested in your posts (I personally find many of them to be fascinating).

[ericmurphy]

Have a look at this diagram, Magellan, which illustrates an element of the simplified version of my model (where fertility is always either 100% or 0):

http://www.planet-deepblu.com/~eric/graphic_links/FirstNonInterfertile.png

Look at the area of the dark green curve that's circled in red. Let's say the very tip of the dark green curve represents the very first individual in population A that cannot interbreed with any member of population B.

Now: what implications does that have, even for this simplified, unrealistic model (unrealistic in its assumption that interfertility is either total or zero)? Keep in mind that with time, the entire dark green region will move to the right, meaning more and more members of population A will be unable to interbreed with any member of population B. At some point, the leftmost edge of that region will be to the right of the "region of interfertility," meaning that no member of A will be able to interbreed with B.

Why can this not happen? Even granting your totally wrong notion that fertility is always either 100% or zero, and that if a member of population A cannot interbreed with one member of B it cannot interbreed with any member of B, why can this not happen?

There are really only three things that need to to be true for my model to work, Magellan:


Sufficient genetic differences between two individuals will lead to a lack of interfertility;
Genetic differences accumulate over time; and
A lack of interfertility between, as distinct from within, populations does not confer a selective disadvantage.


If you want to critique my model, you have to show how at least one of these things cannot possibly be true. If you can't do that, then you cannot possibly argue that my model is unworkable. It's still the case that all of those three things can be true and my model still might still not be correct (meaning it doesn't actually depict what happens in the real world), but if those three things are true, then my model definitely works.

So have at it, Magellan. But if you're going to criticize my model, then criticize my model. Not some other model that doesn't have anything to do with my model.

[ericmurphy]

So Mags: If A is different than B in some way, how exactly is B not different from A in the same way?The difference is Factor X.
If members of Group A in Year 100,000 are the same as members of Group A in Year 1 and Members of Group B differ to members of Group A , then the difference is Factor X.

This post demonstrates, I believe, Magellan's subscribing to a typical creationist error: typological thinking, where there is some sort of Platonic ideal organism—a type—to which other organisms can be compared.

Faid is asking how it's possible B can be different from A if somehow A is not different from B. Magellan's answer: "The difference is factor X" implies that he thinks B possess this "factor X" which makes B not just different from A, but from some Platonic ideal organism that A is identical to. What he's implying (probably without realizing he's implying it) is that there are three different organisms, A, B, and some other organism which I would normally describe as "X" but since X is already in use in this discussion I will call "W."

What Magellan seems to be doing, probably without realizing he's doing it, is comparing A to W and noting that there are no differences, and then comparing B to W and noting that there is a difference—his "factor X."

This is the only way he can possibly think B can be different from A without A also being different from B. What he is really doing is thinking, "B is different [from W], but A is not different [from W], and therefore we can say B is "different" because it has "factor X" but A is not "different" because it doesn't have "factor X."

It's amazing, not to say fascinating, that someone could be this unaware of his own thought processes, but apparently Magellan is. I'm wiling to bet that he could make neither head nor tail of my question, "What's the difference between a duck?"

[Faid]

That would be true if the meaning of Species were 'It's very, very hard for Humans to breed with Chimps.'

MagellanWhy?

Explain yourself for once.


EDIT: Let's try this: When group A and Group B have speciated, is it "very, very hard" for them to interbreed, is it "almost impossible", or is it "impossible"?

No "you tell me", no "evolutionists think". I want to know what YOU think. It should be obvious by your previous descriptions of your 'models', but I want you to irrevocably state it.

[Faid]

The difference is Factor X.
If members of Group A in Year 100,000 are the same as members of Group A in Year 1 and Members of Group B differ to members of Group A , then the difference is Factor X.

Magellan

Did I ask you what the difference is?

No.

Here's the exchange again, unquoted so you can't hide it in multiple quotes:

Here's a question even a child could answer:

Suppose we call Factor X "difference of A+B+C+D+E+F". You have already agreed we can do that.

Now, imagine we have two organisms that differ in A, B, C, D, E and F.

Which of the two organisms has "factor X"?

Straight answer, please.



The different one.



So Mags: If A is different than B in some way, how exactly is B not different from A in the same way?


Do try to actually respond this time, thanks.