Posted on 05/05/2008 11:38:41 AM PDT by blam
Neanderthals were separate species, says new human family tree
A wax figure representing a Neanderthal man on display at a museum. A new, simplified family tree of humanity has dealt a blow to those who contend that the enigmatic hominids known as Neanderthals intermingled with our forebears.
A new, simplified family tree of humanity, published on Sunday, has dealt a blow to those who contend that the enigmatic hominids known as Neanderthals intermingled with our forebears.
Neanderthals were a separate species to Homo sapiens, as anatomically modern humans are known, rather than offshoots of the same species, the new organigram published by the journal Nature declares.
The method, invented by evolutionary analysts in Argentina, marks a break with the conventional technique by which anthropologists chart the twists and turns of the human odyssey.
That technique typically divides the the genus Homo into various classifications according to the shape of key facial features -- "flat-faced," "protruding-faced" and so on.
Reconciling these diverse classifications from a tiny number of specimens spanning millions of years has led to lots of claims and counter-claims, as well as much confusion in the general public, about how we came to be here.
Various species of Homo have been put up for the crown of being our direct ancestor, only to find themselves dimissed by critics as failed branches of the Homo tree.
The authors of the new study, led by Rolando Gonzalez-Jose at the Patagonian National Centre at Puerto Madryn, Argentina, say the problem with the conventional method is that, under evolution, facial traits do not appear out of the blue but result from continuous change.
So the arrival of a specimen that has some relatively minor change of feature as compared to others should not be automatically held up as representing a new species, they argue.
The team goes back over the same well-known set of specimens, but uses a different approach to analyse it, focussing in particular on a set of fundamental yet long-term changes in skull shape.
They took digital 3D images of the casts of 17 hominid specimens as well as from a gorilla, chimpanzee and H. sapiens.
The images were then crunched through a computer model to compare four fundamental variables -- the skull's roundness and base, the protrusion of the jaw, and facial retraction, which is the position of the face relative to the cranial base.
When other phylotogenic techniques are used, the outcome is a family tree whose main lines closely mirror existing ones but offers a clearer view as to how the evolutionary path unfolded.
The paper suggests that, after evolving from the hominid Australopithecus afarensis, the first member of Homo, H. habilis, arose between 1.5 and 2.1 million years ago.
We are direct linear descendants of H. habilis. H. sapiens started to show up around 200,000 years ago.
None of the species currently assigned to Homo are discarded, though.
On the other hand, the Neanderthals are declared "chronological variants inside a single biological heritage," in other words, evolutionary cousins but still a separate species from us.
The squat, low-browed Neanderthals lived in parts of Europe, Central Asia and the Middle East for around 170,000 but traces of them disappear some 28,000 years ago, their last known refuge being Gibraltar.
Why they died out is a matter of furious debate, because they co-existed alongside anatomically modern man.
Some opinions aver that the Neanderthals were slowly wiped out by the smarter H. sapiens in the competition for resources.
Other contend that we and the Neanderthals were more than just kissing cousins. Interbreeding took place, which explains why the Neanderthal line died out, but implies that we could have Neanderthal inheritage in our genome today, goes this theory.
“So, am I right that no direct ancestor for homo-sapiens has ever been discovered? All that were conjectured as that immediate ancestor have been proven not to be?”
I think you would be, however the answer would be, “We just don’t know yet.”
I think that’s my biggest problem with the evolutionists - they keep saying, “It’s just GOT to be right, but we just can’t prove it yet.” At the same time, they denigrate ID’ers.
I used to think that too, but apparently it’s not correct. Lions and tigers can produce fertile offspring, as can cattle and bison (to name a couple of instances). To me, the definition of species is a little fluid, since I KNOW I was taught (and taught when I taught HS biology) that if 2 creatures could breed and produce fertile offspring they were the same species.
susie
It’s just as bad in cosmology.
Hawking even had to come up with some sort of yo-yo theory to explain the expanding universe, since he is a hardcore materialist.
The liger is pretty much my favorite animal.
This is the admition I was looking for. ;)
He also speculated on a totally goofy and unsupported "multiple universes" theory in a effort to deal the anthropic principle.
The tame silver fox was never interbred with other canine species, it was selective breeding within foxes. The important proof of that experiment was that wild canines could be selectively bred into tame canines and that foxes contain the same genetic variations that dogs and wolves have.
Yeah, the claim was made on one of those semi-educational cable TV shows. Supposedly after they got tame wolves, they wanted some more dog-like trainability and temperament, so they experimented with some hybrids. I can't vouch for their honesty, however. :)
Don’t get me wrong - Hawking is BRILLIANT.
But he’s handicapped by his absolute insistence on materialism.
If you have a blindspot that you absolutely refuse to explore, even though the evidence points there, you’re going to start having to twist yourself in knots to avoid that conclusion. And, I suppose the more brilliant you are, the more convoluted those knots are going to be.
I thought that breed was from dingoes or jackals or some other wild dog.
This is true, since the terms are all what we humans use to try to categorize genetic differences. As we learn more, we keep redefining the terms we use. For example, the more we learn about the quality we call "intelligence," we find that some animals are not as "dumb" as we once assumed.
On the other hand, we find that the sub-species known as Marxist/Socialist, colloquially known as "liberal," is dumber than many animals. :)
The Russian tame foxes? No, the Russians experimented with foxes to try to produce dog-like characteristics, but they didn't use any other wild species except foxes. The TV show I referred to centered on one man in Russia who was trying to come up with a tame fox breed that could do a better job than dogs at sniffing out illegal substances and explosives. His foxes or fox hybrids now patrol Russian airports.
The russians bred tame foxes that ended up looking like dogs. I don’t remember them introducing dogs into the breeding program.
Two separate species may well be CAPABLE of interbreeding and producing fertile offspring but if they do not, and according to genetic research have not for several thousand years; they are a separate species even if you can successfully breed them in captivity.
I think maybe they now consider dogs and wolves to be the same species.
susie
No, not that one but the one were they kept intermixing different breeds for use in crime fighting and bomb sniffing. They found that it kept maintaining too much of its wild side from its breeding with whatever wild dog they used and had to breed in more passive tame breeds.
Here it is, they used a turkmen jackal for it;
http://europuppyblog.com/item/2008/03/russian-airlines-develop-a-super-sniffing-dog-breed
Actually, tiger lion crosses can be fertile. Also bison and cattle (beefalo). I think they have changed the definition of species in recent years as information became known.
susie
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