The problem of what is a species when the number of different species? is increasing

[shunyadragon]

Recently the number of different species, sub-species, variations have been increasing exponentially. In the past identification of species was fairly simple, and of course over time more and more fossils have been discovered. At one time feathered bird like dinosaurs were based on a few fossils now there thousands. Fifty years ago the fossils of human would fit in a card board box, and now they could fill a museum. The following article addresses the problem with recent discoveries of dinosaurs. The number of dinosaur fossil discoveries have increased exponentially, and new species, sub-species, varieties and genera of the dinosaurs has greatly increased.

The problem of what is a species has been also compounded by a closer look at the diversity in today's world. More on this, but first the article . . .

Source: http://bgr.com/2018/02/20/dinosaur-discovery-fossils-changing-what-we-know/

New dinosaurs are being discovered in record numbers, and it’s changing everything we thought we knew

“It’s a nice little paper that shows that in the last 20 years, the number of dinosaur genera named, as well as the number of specimens of those genera, has increased greatly,” Jonathan P. Tennant, co-author of the work, explains. “This has profound impacts on our understanding of dinosaur diversity, especially as these discoveries are unevenly spread over time and space. There are still huge gaps in our knowledge of the fossil record, and areas in space and geological time where the rapid pace of discovery is changing much of what we thought we knew about dinosaurs.”

You don’t have to look far to find examples of how an increase in dinosaur discoveries has shifted our knowledge. A few decades ago, the idea that some land-dwelling dinosaur species were covered in feathers was laughable at best. Crafty hunters like the velociraptors in Jurassic Park are depicted as leathery beasts, but we now know that the creatures were largely covered in plumage. Likewise, the mighty Tyrannosaurus rex was long thought to be the ultimate predator, but more recent discoveries have suggested it may have also been a scavenger, feasting on already-dead carcasses rather than hunting for a fresh feast when it was hungry.

There’s no telling what discoveries lie under the next rock, but scientists are painting a prehistoric picture faster and with more detail than ever before, and it’s quite exciting.

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It is an interesting paper with neat graphs showing the exponential number of discoveries since 2000.

For a change this is a REAL science thread, and no rabbit fossils were found. The pile of non-existent evidence is getting deeper.

[shunyadragon]

The species problem - The concept of Charles Darwin proposed that science would eventually determine how one species would evolve into another, but as the knowledge of genetics, and numbers of fossil discoveries increased the problem of what a species became less and less clear. This represent the major change in the science of evolution has advanced since Charles Darwin.

Source: https://en.wikipedia.org/wiki/Species_problem

The species problem is the set of questions that arises when biologists attempt to define what a species is. Such a definition is called a species concept; there are at least 26 recognized species concepts. A species concept that works well for sexually reproducing organisms such as birds is useless for species that reproduce asexually, such as bacteria. The scientific study of the species problem has been called microtaxonomy.

One common, but sometimes difficult, question is how best to decide which species an organism belongs to, because reproductively isolated groups may not be readily recognizable, and cryptic species may be present. There is a continuum from reproductive isolation with no interbreeding, to panmixis, unlimited interbreeding. Populations can move forward or backwards along this continuum, at any point meeting the criteria for one or another species concept, and failing others.

Many of the debates on species touch on philosophical issues, such as nominalism and realism, and on issues of language and cognition.

The current meaning of the phrase "species problem" is quite different from what Charles Darwin and others meant by it during the 19th and early 20th centuries. For Darwin, the species problem was the question of how new species arose. Darwin was however one of the first people to question how well-defined species are, given that they constantly change.

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[rogue06]

If evolution were true we should expect to find gray areas where one species splits into separate species. Same goes for higher taxonomic levels.

[shunyadragon]

If evolution were true we should expect to find gray areas where one species splits into separate species. Same goes for higher taxonomic levels.

Based on the genetic and physical evidence today and in geologic history the taxonomic nature of life is dominantly gray areas.

Examples: (1) The difference between feathered dinosaurs and birds. (2) The history of Homo Sapiens (sapiens?) as a species separate from our ancestors.

I believe the evidence demonstrates evolution is a continuous process without the artificial boundaries some may describe as species, and other taxonomic boundaries.

". . . I was much struck how entirely vague and arbitrary is the distinction between species and varieties . . .”
—
Charles Darwin, On the Origin of Species

[rogue06]

Based on the genetic and physical evidence today and in geologic history the taxonomic nature of life is dominantly gray areas.

Examples: (1) The difference between feathered dinosaurs and birds. (2) The history of Homo Sapiens (sapiens?) as a species separate from our ancestors.

I believe the evidence demonstrates evolution is a continuous process without the artificial boundaries some may describe as species, and other taxonomic boundaries.

". . . I was much struck how entirely vague and arbitrary is the distinction between species and varieties . . .”
—
Charles Darwin, On the Origin of Species

A considerably better example would be the transition from "reptiles" to mammals. There are are a legion of examples that can be offered and there is a good deal of controversy among paleontologists over whether this or that creature should be best classified as a mammal-like reptile or a reptile-like mammal.

[TheLurch]

I think the other thing is that the significance of these transitions is only obvious in retrospect. If birds weren't around today, feathers would just be a variant feature of some dinosaurs. If we were living in the period where they first started appearing, feathers might seem something like trunks on elephants - a bit unusual, but just part of the spectrum of mammals.