Same Sex Marriages and Sexual Orientation

[oxmixmudd]

Are you aware that it's quite common for evolution to select for a trait until it reaches a certain percentage of the population and then limit it beyond that?

Any time some particular trait becomes fully dominant in a population group (let's say, for example, the tendency to be kind and generous and altruistic toward all), there will be strategies that exploit that trait for minority gain (e.g. being a selfish jerk and hording all the group's resources). So evolution will start selecting for the new exploitative strategy as soon as it appears as it has superior survival value over the existing dominant strategy. But once such new minority strategies reach a decent minority percentage of the population (e.g. 10%), they become less and less effective, because the majority becomes aware they exist and starts countering them (e.g. the altruistic people learn to be on the lookout for those stealing the group's resources for themselves, because they've seen it happen before). So the society reaches an equilibrium state where the system is stable with a number of different traits that evolution has selected for up to certain points all at different percentages within the group.

Some have theorized, for example, that this is why a minority of people are left-handed: Because if a small percentage of the population is different handed to the majority, in any one-on-one physical combat they will have the element of surprise from being able to strike with a hand different to what the other person is expecting, and hence win the fight (and not die in it / win the rights to breed with the females etc). But once too many people become left-handed, the right-handers know to be on the lookout for the possibility, so it stops being a survival advantage over being right-handed and thus evolution ceases selecting for it and the percentage of people who are left-handed thus doesn't grow beyond 10% of the population.

I would tend to assume that homosexuality is one of those traits that evolution favors up to a certain percentage of the population. From the study on birds I cited in my earlier post, it appears that the percentage of homosexual males that evolution favors in a population is proportional to the polygamy within the population, and the percentage of homosexual females it favors is inversely proportional to the polygamy.

Anyway, the point is, that evolution can select for something due to its survival advantage without it eventually becoming a dominant trait within the species, because the trait's survival value decreases if there is too much of it within the population and so evolution ceases selecting for it at that point and a stable equilibrium is reached with different traits being present within the population at different levels. This is something that happens fairly regularly. (Again, this is why nothing about evolution is really 3rd grader stuff)

I would not call what you are describing here as 'selecting for', and I defined what I meant by 'selecting for'. There are several factors. Some traits are neither good nor bad, but genetically they are dominant or recessive. So they get favored even though one or the other really is not a specific advantage or disadvantage. Left-handedness is just such a property. It takes two people with a left-handed gene to make a left handed kid. So in general, the probablility of being left handed is about 25%. But there are other cultural factors that reduce that. One interesting factor is that in the long lost world one of the factors discouraging left handedness was the simple fact that one ate with one hand (the power hand) and one cleaned oneself after going to the bathroom with the other. So there would then be a good bit of pressure for everyone to use the same hands for each activity, and right handedness being the dominant trait it won out.

Evolution selects for traits that (in sum) give an advantage. It selects against traits that are (in sum) take away from survivability. But there is a lot of stuff that just isn't that clear. Anything that is not immediately destructive can be tolerated in part - until it reaches a sufficiently large percentage that it becomes destructive. same-sex attraction is definitely such a trait. It can be tolerated, but it can't become the primary orientation of the species (at least not in a natural environment). And that is the context of my statement. Evolution will not select FOR same-sex attraction for a species that has sexual reproduction. If same-sex attraction becomes a dominant trait, the species dies.

Secondarily, whatever genetic elements cause same-sex attraction are in essence self-limiting independent of selective pressure in that they can't be propagated unless:

1) the same-sex members actually engage in some sort of hetero-sexual activity. This happens (prior to the capacity to do artificial insemination) if they aren't exclusively same-sex (bi), or if cultural pressure coerces* them to limit acting on their same-sex attraction and they marry and have children. Any time in history prior to the last 50 years or so engaging in hetero-sexual activity would have meant mating with the opposite sex. Today women can become pregnant by other artificial means.
2) the genetic components that sometimes manifest as same sex attraction actually confer other survival advantages and only sometimes come together in a way that produces same-sex attraction. This would be something like the observations that females that have a greater capacity to produce children also have a higher incidence of same-sex attracted children. That there is something in the genes that let a woman bear more children that also can end up producing same-sex attraction.

Both types of persistence enabling circumstances can and do exist and allow what is on the surface a trait contrary to the ultiimate survival of a species to persist in the population at a small percentage without harmful effect.


Jim

* ao here is a paradoxical situation. If same-sex attraction is inherited, then cultural pressure that makes a same-sex individual 'hide' in a hetero-sexual relationships or relationships, making children as a consequence, actually HELPS same sex attraction survive by allowing same-sex individuals to pass their genes on rather than their inclinations resulting in an end to their genetic uniqueness.

[Starlight]

Left-handedness is just such a property. It takes two people with a left-handed gene to make a left handed kid. So in general, the probablility of being left handed is about 25%.

There are no known genes for left-handedness, and the percentage of the population with it is about 10%. To the extent that it might be genetic, it must involve a dozen or more genes working together (simpler models have been ruled out by computational analysis of genetic data), it is definitely not a single recessive gene like you're suggesting.

As a result, left-handedness seems an apt comparison for homosexuality: It is a trait that about 10% of our population has, and seems innate to the people who have it, but we don't have any genetic causes of it identified yet and if they exist they're really complex because they can't be straightforwardly found in existing genetic sequence data. Those things are true of both left-handedness and homosexuality.

But there is a lot of stuff that just isn't that clear. Anything that is not immediately destructive can be tolerated in part - until it reaches a sufficiently large percentage that it becomes destructive. same-sex attraction is definitely such a trait.

That seems right. It seems that, like left handedness, evolution has favored approximately a 90% / 10% ratio of majority sexuality / handedness versus minority sexuality / handedness. Presumably if we had a full model of all the factors in play, and how the traits conferred comparative survival advantage at different levels in the population, then we could predict that ratio.

Evolution will not select FOR same-sex attraction for a species that has sexual reproduction.

It would select for it if the presence of the trait in the species was below 10%, and select against it if the presence of the trait was above 10%, and have no selective preference if the level of the trait was at the equilibrium point of 10%. (Assuming that 10% is the equilibrium rate. We're ignoring bisexuality here, of course, which we shouldn't.)

To the extent that you seem to want to use these facts as some sort of a pathway to arrive at morality, it seems to me that unless you are prepared to make the claim that being left handed is wrong because it is a minority trait, you are not going to be able to claim that being gay is wrong. It is also a bit weird to me that you are flailing about for strange arguments to try to show the immorality of homosexuality. You're getting dangerously close to magnets prove gay marriage is wrong territory.

[seer]

Well in the study on black swans they found that chicks raised by two male swans had a higher survival rate than chicks raised by heterosexual couples, because the two males were stronger and able to feed from / defend more territory and hence feed the offspring better. So evolution seems to have selected as a result for a pretty high rate of male-male couples (25%) among black swans.

Yes but two male swans can't have chicks in the first place, no matter who raises them after. Second, with gay couples one parent always has to be a step parent, and step parents on average do not support the child as well as a biological parent.

In humans? The answer is a bit less clear. However, it's worth noting that in any polygamous society (and much of human history seems to be polygamous) you have spare males. Those males have to do something with their time. It seems likely a general advantage to the society that they be content with enjoying each others company rather than killing each other or constantly challenging the dominant male (who has the harem of females) for dominance.

That is just silly... Perhaps it was selected for because gays were better at decorating our caves...

[Starlight]

Yes but two male swans can't have chicks in the first place, no matter who raises them after.

I'm not sure what the relevance of that observation is. Evolution can still select for the tendency of males to pair up, due to the superior survival rates of the chicks raised by them.

Second, with gay couples one parent always has to be a step parent

At the moment, though technology looks set to change that within a few years. They can always adopt of course.

and step parents on average do not support the child as well as a biological parent.

I am not aware of any evidence that this claim is true. Adoptive parents on average are known to do slightly better than biological parents on average (barriers to adoption mean that only people who really want a child and can afford to support one become adoptive parents). I am not aware of specific research concerning step parents, but there have been plenty of studies in general that found that same-sex parents were as good as biological parents.

Perhaps it was selected for because gays were better at decorating our caves...

I am skeptical of the idea that gay men have any special artistic talent. The ones I know, at least, have far lower than average artistic talent. Maybe it's simply that heterosexual men often feel pressured to suppress what artistic talent they have because it's "not manly", while gay men don't feel that same pressure?

[carpedm9587]

How does homosexuality have any short or long term advantage?

I would be guessing at best. I have no data and the research is in its infancy. There's an article that talks about it here. It's interesting, but I don't think it is by any means conclusive.

[carpedm9587]

Yes but two male swans can't have chicks in the first place, no matter who raises them after. Second, with gay couples one parent always has to be a step parent, and step parents on average do not support the child as well as a biological parent.

This strikes me as a "Disney" claim. Do you have any data to support the claim that step parents, on average, do not support their child as well as a biological parent? Indeed, in an adoption situation, neither parent is biological. But adoptive parents explicitly choose to be parents, and have to pass a battery of tests and evaluations to be accepted as adoptive parents. Biological parents become parents without any such screening.

I would assess your claim here as "groundless," unless you can provide some studies that affirm it...?

That is just silly... Perhaps it was selected for because gays were better at decorating our caves...

Actually, there is merit to the claim. In a population with excess, single males, there does tend to be higher violence levels and a greater propensity for war and rebellion. There are several papers on this and a lot of history to support it. It is currently a significant issue in China and India. Male homosexuality would counter this dynamic.

[carpedm9587]

To the extent that you seem to want to use these facts as some sort of a pathway to arrive at morality, it seems to me that unless you are prepared to make the claim that being left handed is wrong because it is a minority trait, you are not going to be able to claim that being gay is wrong. It is also a bit weird to me that you are flailing about for strange arguments to try to show the immorality of homosexuality. You're getting dangerously close to magnets prove gay marriage is wrong territory.

This is a point I have been attempting to make for some time now. Jim seems to be trying to arrive at morality by statistics. I saw that in his attempt to go down the (now abandoned?) "birth rate decline" argument. I do not see how that would ever work.

[seer]

I'm not sure what the relevance of that observation is. Evolution can still select for the tendency of males to pair up, due to the superior survival rates of the chicks raised by them.

But two males could not produce the offspring in the fist place. And I'm not sure how much survival value two males would have over a biological male and female. I really don't think it would matter in the least to the wolf. And you are assuming that the two male swans are in a same sex relationship. Is that the case?

At the moment, though technology looks set to change that within a few years. They can always adopt of course.

That doesn't presently change my point.

I am not aware of any evidence that this claim is true. Adoptive parents on average are known to do slightly better than biological parents on average (barriers to adoption mean that only people who really want a child and can afford to support one become adoptive parents). I am not aware of specific research concerning step parents, but there have been plenty of studies in general that found that same-sex parents were as good as biological parents.

For instance:

Fatal batterings of small children

This most severe category of child maltreatment exhibits Cinderella effects of the greatest magnitude: in
several countries, stepparents beat very young children to death at per capita rates that are more than
100 times higher than the corresponding rates for genetic parents.

Econometric analyses of large data bases such as the U.S. Panel Study of Income Dynamics provide
one sort of evidence: controlling for the family’s economic means, U.S. stepchildren receive reduced
investment in the form of support for higher education, routine medical and dental care, and even food
(e.g. Case et al. 2000; Case & Paxson 2001; Zvoch 1999). Surveys that ask people directly about
parental support tell the same story: according to both the parents and the children, stepparents withhold
investment relative to genetic parents (e.g. Anderson et al. 1999a,b; White 1994). Also of interest in
this context is Ferri’s (1984) finding that both the mothers and stepfathers in British stepfamily homes
expressed low aspirations for the children’s education, lower even than those of single mothers of lesser
means.


https://pdfs.semanticscholar.org/372...ac3f10c712.pdf

I am skeptical of the idea that gay men have any special artistic talent. The ones I know, at least, have far lower than average artistic talent. Maybe it's simply that heterosexual men often feel pressured to suppress what artistic talent they have because it's "not manly", while gay men don't feel that same pressure?

The point Star, is that my example for selection is just as silly or meaningless as yours.

[seer]

This strikes me as a "Disney" claim. Do you have any data to support the claim that step parents, on average, do not support their child as well as a biological parent? Indeed, in an adoption situation, neither parent is biological. But adoptive parents explicitly choose to be parents, and have to pass a battery of tests and evaluations to be accepted as adoptive parents. Biological parents become parents without any such screening.

I would assess your claim here as "groundless," unless you can provide some studies that affirm it...?

As far as the step parents I linked one study to Star, and I said nothing about adoptive parents

Actually, there is merit to the claim. In a population with excess, single males, there does tend to be higher violence levels and a greater propensity for war and rebellion. There are several papers on this and a lot of history to support it. It is currently a significant issue in China and India. Male homosexuality would counter this dynamic.

So men having sex with each other makes them less violent? If that is true how come men in China and India are not warring and rebelling all over the place - certainly homosexuality is not widely accepted, or even practiced in either country. And why would all these frustrated straight men suddenly turn gay? You are just making stuff up.

[carpedm9587]

As far as the step parents I linked one study to Star, and I said nothing about adoptive parents

True. However, you brought up "step-parents" in the contexts of homosexuality. For female homosexual couples, one is usually a "step-parent," but they usually immediately move to adopt, with all of the requisites involved with that. For male homosexual couples, adoption is the usual course. So they are better compared to adoptive parents than step parents, hence my response.

And your study does not split out the two types of step-parents: those who adopt their step children and those who do not. So you're kind of muddying the waters with your claims.

So men having sex with each other makes them less violent? If that is true how come men in China and India are not warring and rebelling all over the place - certainly homosexuality is not widely accepted, or even practiced in either country. You are just making stuff up.

Actually, I said nothing of the kind. I merely observed that homosexuality would reduce the "single, unattached male" population. That is the population historically linked to rebellion and violence. It is a reason why it might be a selected-for trait. When war and rebellion occur, the population most decimated will be the single, unattached males. You asked for how homosexuality could be a selected-for trait. This is a perfectly reasonable possibility.

And I also said we have little/no data to work with, so I would be guessing at best. This is my best guess.

[seer]

True. However, you brought up "step-parents" in the contexts of homosexuality. For female homosexual couples, one is usually a "step-parent," but they usually immediately move to adopt, with all of the requisites involved with that. For male homosexual couples, adoption is the usual course. So they are better compared to adoptive parents than step parents, hence my response.

In those cases one parent is still a step parent as opposed to a biological parent. So no they are not better compared to adoptive parents where neither are biological parents.

And your study does not split out the two types of step-parents: those who adopt their step children and those who do not. So you're kind of muddying the waters with your claims.

No, the difference is clear between biological and non-biological parenting.

Actually, I said nothing of the kind. I merely observed that homosexuality would reduce the "single, unattached male" population. That is the population historically linked to rebellion and violence. It is a reason why it might be a selected-for trait. When war and rebellion occur, the population most decimated will be the single, unattached males. You asked for how homosexuality could be a selected-for trait. This is a perfectly reasonable possibility.

And I also said we have little/no data to work with, so I would be guessing at best. This is my best guess.

No you said there was merit to the claim. Why would straight men who want women suddenly be satisfied or less violent by having sex with a man - or even want to have sex with a man?

[carpedm9587]

In those cases one parent is still a step parent as opposed to a biological parent. So no they are not better compared to adoptive parents where neither are biological parents.

Except that the norm (in my experience) is that they adopt their partner's child.

No, the difference is clear between biological and non-biological parenting.

As an adoptive parent, your language is more than a little offensive.

No you said there was merit to the claim. Why would straight men who want women suddenly be satisfied or less violent by having sex with a man - or even want to have sex with a man?

No one said they would. You don't appear to be understanding the argument. Let me do it with some completely made-up numbers (assuming 5% initial homosexuality rate).

Heterosexual female population: 950
Homosexual female population: 50
Heterosexual male population: 1900
Homosexual male population: 100

Assuming everyone partner's up, all homosexuals partner up and 950 of the 1900 males find a mate, leaving 950 unpartnered males. War/rebellion ensue and the unpartnered males make up the vast majority of the fighting force. They suffer a 50% morality rate. Post rebellion:

Heterosexual female population: 950
Homosexual female population: 50
Heterosexual male population: 1425
Homosexual male population: 100

Before the rebellion, homosexual males represented 5% of the male population. Post conflict, they represent 6.6% of the male population. Ergo, they have been "selected for."

This is the dynamic to which I was referring.

[oxmixmudd]

There are no known genes for left-handedness, and the percentage of the population with it is about 10%. To the extent that it might be genetic, it must involve a dozen or more genes working together (simpler models have been ruled out by computational analysis of genetic data), it is definitely not a single recessive gene like you're suggesting.

As a result, left-handedness seems an apt comparison for homosexuality: It is a trait that about 10% of our population has, and seems innate to the people who have it, but we don't have any genetic causes of it identified yet and if they exist they're really complex because they can't be straightforwardly found in existing genetic sequence data. Those things are true of both left-handedness and homosexuality.

It may well be that handedness and same-sex orientation are similar in how they come about. I was not trying to say exactly what the specific genetic cause of handedness was, just that it is not a dominant trait.

However, handedness, unlike same-sex attraction - does not have the potential to affect the number of children created in a given generation, whereas same-sex attraction does. handedness also doesn't have the potential to increase the incidence of disease in a population, whereas sexual activities associated with male same-sex attraction do. But as a genetic analogue I can see the possibility they are similar.

That seems right. It seems that, like left handedness, evolution has favored approximately a 90% / 10% ratio of majority sexuality / handedness versus minority sexuality / handedness. Presumably if we had a full model of all the factors in play, and how the traits conferred comparative survival advantage at different levels in the population, then we could predict that ratio.

No disagreement there. However, I would point out that if our ideology does not allow us to pursue what all the factors might be, we will likely never know the answer to that question. The left wants to push the evidence away from nurture, the right wants to push the evidence away from genetics. The hot button nature of the issue, its conflict with the moral code of the 3 major world religions, and just the general close mindedness demonstrated so clearly on both sides in this thread I believe means we will not know enough about this issue to make such a call for a very, very long time, if ever. The problem here is that if there are elements that can be destructive in how we structure our society around the issue, we won't know until many have been hurt by those mistakes. Same as with AGW and a whole host of scientific issues where all possible elements of the issue simply can't be explored because of the politics and ideological impacts of certain conclusions.

For example - none of you actually know what I think about this issue. But I've been arguing against the PC side of the issue. Most of you that are pro same-sex acceptance come hell or high-water think I am rabidly homophobic. But that is just because of your own rabid ideological biases. The same thing happens anytime I raise for discussion any element that might not support AGW - even though think AGW is real - I get labelled a 'climate change denier'. Most people in this world simply are incapable of a rational, unbiased discussion of any topic that has the potential to directly affect their world-view.

It would select for it if the presence of the trait in the species was below 10%, and select against it if the presence of the trait was above 10%, and have no selective preference if the level of the trait was at the equilibrium point of 10%. (Assuming that 10% is the equilibrium rate. We're ignoring bisexuality here, of course, which we shouldn't.)

To the extent that you seem to want to use these facts as some sort of a pathway to arrive at morality, it seems to me that unless you are prepared to make the claim that being left handed is wrong because it is a minority trait, you are not going to be able to claim that being gay is wrong. It is also a bit weird to me that you are flailing about for strange arguments to try to show the immorality of homosexuality. You're getting dangerously close to magnets prove gay marriage is wrong territory.

I would never posit that same-sex attraction is wrong BECAUSE it is a minority trait. That is ridiculous. And the fact that you would think I might take a tack like that is just your own bias and/or lack of knowledge of me shining through. And no, I'm not getting dangerously close to anything. I haven't even tried to argue that point yet - not even sure at this point if I will for the simple reason that a rational discussion of any possible reasoning in that direction is simply impossible in this (or proabably any) forum. My reluctance so far is not based on a lack of ideas, but a lack of desire to take on the rabid hostility and irrational labeling that would accompany such an attempt. Bottom line - none of you are even remotely capable of an objective discussion on this issue. So I have to decide is if there is a sufficiently high probability I will learn something sufficiently useful in such a discussion that it will be worth wading through the mountain high pile of insults and derogatory statements I would have to wade through in such a discussion.


Jim

[seer]

Except that the norm (in my experience) is that they adopt their partner's child.


As an adoptive parent, your language is more than a little offensive.

Why? You may be a fine non-biological parent, I was to my step son. That does not mean statistically that is the case.

No one said they would. You don't appear to be understanding the argument. Let me do it with some completely made-up numbers (assuming 5% initial homosexuality rate).

Heterosexual female population: 950
Homosexual female population: 50
Heterosexual male population: 1900
Homosexual male population: 100

Assuming everyone partner's up, all homosexuals partner up and 950 of the 1900 males find a mate, leaving 950 unpartnered males. War/rebellion ensue and the unpartnered males make up the vast majority of the fighting force. They suffer a 50% morality rate. Post rebellion:

Heterosexual female population: 950
Homosexual female population: 50
Heterosexual male population: 1425
Homosexual male population: 100

Before the rebellion, homosexual males represented 5% of the male population. Post conflict, they represent 6.6% of the male population. Ergo, they have been "selected for."

This is the dynamic to which I was referring.

Really, I have no idea what your point is. So after the conflict, since more straight males were killed, we have more gays. But that would be short lived as the "normal" population reconstituted itself. And what makes you think that gay men would partner up more than the average straight guy?

[carpedm9587]

I would never posit that same-sex attraction is wrong BECAUSE it is a minority trait. That is ridiculous. And the fact that you would think I might take a tack like that is just your own bias and/or lack of knowledge of me shining through. And no, I'm not getting dangerously close to anything. I haven't even tried to argue that point yet - not even sure at this point if I will for the simple reason that a rational discussion of any possible reasoning in that direction is simply impossible in this (or proabably any) forum. Bottom line - none of you are even remotely capable of such a discussion.

Jim

The bold part caught my eye. You do this a lot, Jim. If you don't want to have a discussion, then don't have it. It's not a big deal. But it seems quite disingenuous to keep telling everyone that you're not engaging in a discussion because the other people are not capable of it. Frankly, I cannot see how you can possibly make a moral argument in this direction. Perhaps the problem is not so much that we are not capable of the discussion as it is that the argument is very likely to fail. But you will never know if it is going to succeed or fail if you continually refuse to put forward the argument for examination. An argument that is never examined by anyone but the holder will never truly be tested; you will be much less likely to find your own errors. If you truly want to test an argument, put it forward to people most likely to disagree. You can be sure they (we) will look for every chink and weakness in the argument. If it survives that examination, then you know you have something to work with.

Frankly, if it survives that examination, an honest evaluator would be forced to change their initial position as a consequence. That will never happen if you keep ducking (dare I say dodging? ) the discussion.