An Anthropological Question

[Bicycle Bill]

According to the American Museum of Natural History, we have, based solely on the fossil record, identified and named something like SEVEN HUNDRED DIFFERENT species of extinct non-avian dinosaurs.  In many cases, the differentiation between one species and another are very ephemeral, such as the existence of, size of, or placement of a single bone.

And even in modern times, we give similar specimens of existing non-extinct animals — like beetles in the order Coleoptera — based on very minuscule differences such as wing structure, coloration, or whether said beetle does or does not have protrusions a la the Long-horned beetle, (family Cerambycidae), of which there are something like 25000 different species within that one group alone?

And we've already identified and named several antecedents of modern-day man — Neanderthal man, Cro-magnon man, Java man, Peking man, Homo habilis, Australopithecus, just to name a few.

So why is it that, currently, each and every member of a group of SEVENTY-SEVEN HUNDRED MILLION (current population of the world, give or take a few) tool-using, large-brained, bipedal naked apes are still, one and all, considered to be members of one single, same species?  Doesn't it make more sense that over the past several millennia that Homo sapiens wouldn't have also developed differences that could easily be shown through bone structure or other significant differences?  Or are we just being deliberately obtuse when it comes to studying ourselves?

-"BB"-

[Burning Petard]

OMG. Bill I think you have a major scientific breakthrough ! Every individual person living today is of a Different Species! There is certainly differences in bone structure of the same degree as you cite for these different dinosaurs.

Snailgate.

[datsunaholic]

I would say that the "existence" of a different bone would usually differentiate species, whereas size may just be an outlier.

Had diverging evolution continued within Homo Sapiens, in millions of years them MAYBE there would have been separate species. Similar but different species exist mainly due to geographical separation causing divergent evolution, OR different species evolved to be similar due to similar circumstances.

One of the main traits that defines a species is the ability to breed and produce fertile offspring. That's why domesticated dogs (Canis Lupis Familiarus) are all one species even though many breeds (which were created via animal husbandry/selective breeding) have extremely different appearances. But that wasn't natural evolution.

[Sue U]

Not all of the now-extinct hominins were our ancestors; some were our "cousins" on this branch of the hominid tree. And some (like the neanderthals and some other recently identified lineages) lived contemporaneously with more-or-less modern homo sapiens. But dinosaurs were around for 165 million years and insects have been here for about 480 million years; our line separated from chimpanzees only 5 million years ago. Homo sapiens sapiens has only been around a few hundred thousand years at most. Genetic drift and speciation takes time; what's your rush?

ETA:

Also, because humans of different clines insist on interbreeding with each other rather prolifically, there may never be a future branching of the human line.

[ex-khobar Andy]

There is a story about the British biologist JBS Haldane, who revolutionized our thinking of evolution and gave it a firm mathematical basis. I am reminded of that by BB's initial post:

There is a story, possibly apocryphal, of the distinguished British biologist, J.B.S. Haldane, who found himself in the company of a group of theologians. On being asked what one could conclude as to the nature of the Creator from a study of his creation, Haldane is said to have answered, “An inordinate fondness for beetles.”

[BoSoxGal]

Why are some people so desperate to differentiate themselves as ‘other than’ their fellow humans?

One of the root causes of human suffering.

[dales]

Non-binary ?

[Gob]

Also, because humans of different clines insist on interbreeding with each other rather prolifically, there may never be a future branching of the human line.

Does that include Redruth? I've seen things walking upright there which in no way can be of our species.

[Bicycle Bill]

One of the main traits that defines a species is the ability to breed and produce fertile offspring. That's why domesticated dogs (Canis Lupis Familiarus) are all one species even though many breeds (which were created via animal husbandry/selective breeding) have extremely different appearances. But that wasn't natural evolution.

According to my research, domesticate dogs (Canis lupus familiarus) and the wolf (Canis lupus) are interfertile, which means that can interbreed to create the so-called 'wolf-dog', and that the offspring of such a pairing are fertile and capable of reproducing themselves.  I believe this has also happened in the wild with fish (resulting in things like the 'tiger muskellunge' and a couple of various strains of trout), as well as domesticated hogs breeding with wild hogs, resulting in a crossbred and prodigiously fertile invasive species known colloquially as "feral hogs".

So I believe that if there were, in fact, any specimens of Homo erectus or Homo neanderthalensis still running around (and there apparently are; I have been singled out by at least two members of this board as falling into the latter classification, and they're edumacated people so they oughta know, right?), they would and could be capable of mating with and creating fertile offspring with Home sapiens sapiens.

-"BB"-

[Sue U]

Genetic science has already proven that our line of hominins interbred with Neanderthals, Denisovans and other now-extinct populations, and that most humans today have an admixture of DNA as a result. Unless you are solely of sub-Saharan African descent, you are literally the product of this cross-breeding.

[Sue U]

Also, because humans of different clines insist on interbreeding with each other rather prolifically, there may never be a future branching of the human line.

Does that include Redruth? I've seen things walking upright there which in no way can be of our species.

Well, it's Cornwall, so they could have interbred with the Welsh.

[Gob]

OOh, bitch!

[Sue U]

OOh, bitch!

Oh come on, you were begging for it!

[Gob]

[Long Run]

The reference to dogs seems apt -- an incredible variety of breeds are considered one species.

[Burning Petard]

"One of the main traits that defines a species is the ability to breed and produce fertile offspring" Then again, perhaps dinosaurs are all one species
because none of them have the ability to breed.

Me, I always declare my race to be 'human" and if that is not acceptable I check 'mixed' or 'other'. I really get confused when asked for ethnicity.

snailgate