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Australian Aboriginal DNA Suggests 70,000-Year History
brindafella writes with a link to an abstract at the journal Science that says "Scientists have obtained a DNA genomic sequence from a 100-year-old, voluntarily donated hair sample from a full-blood Australian Aboriginal man. [Analysis of the hair] shows 'Aboriginal Australians are descendants of an early human dispersal into eastern Asia, possibly 62,000 to 75,000 years ago. This dispersal is separate from the one that gave rise to modern Asians 25,000 to 38,000 years ago. ... [Their] findings support the hypothesis that present-day Aboriginal Australians descend from the earliest humans to occupy Australia, likely representing one of the oldest continuous populations outside Africa.' A news story gives more detail."
out of africa!
Great! Now if us Australians can stop treating them like second class citizens...
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No. The evolution of the hominid family is WAY more complex than that. Basically you have a set of inter-breeding semi-distinct populations from 4 million years ago all the way to circa 30,000 years ago (maybe even as late as 20,000 years ago based on some finds of neanderthal tools). All the way through most of the populations would have been genetically similar enough to interbreed successfully (especially after H. ergaster and H. erectus 2 million years ago). H. heidelbergensis, neanderthalensis, and sapiens likely all interbred. Neanderthals were Europeans descendants of an earlier H. ergaster or H. heidelbergensis exodus from Africa. Australian aboriginals, like all modern humans, would be predominantly H. sapiens, with differing traces from the interbreeding with earlier populations.
Moreover, you've misunderstood the data on the Cro Magnon man. Modern humans arrived in EUROPE (Cro-Magnon is the place in France where skeletons were found) 35,000 years ago (as best as we can tell). They appear in Africa almost 200,000 years ago, and in the Middle East before 60,000 years ago.
They're probably wrong. The evolutionary tree of Homo sapiens has four major branches: Aborigines, Eurasians, Africans, and Khoisan. The Aborigines and Eurasians are each other's closest relatives, Africans are more distantly related, and the Khoisan (bushmen) are the most ancient branch of our evolutionary tree. All four groups have the mental hardware to do things like use language, create artwork, and make sophisticated stone tools. While it's concievable that they each evolved that capability independently, Occam's razor says it's simpler to assume that it evolved once, than to assume it happened four separate times. And since Aborigines were around 70,000 years ago, this hardware package- what we'd called the "behaviorally modern" human- would have appeared by that time.
Consistent with this idea, you get cave paintings in Australia around 50,000 years ago, as soon as the Aborigines show up there. And you get cave paintings and sophisticated stone tools in Europe around 30,000 years ago, when the Eurasians move out of Africa. In this scenario, the reason sophisticated stone tools and cave art don't show up earlier is that advanced humans were restricted to Africa. If so, then we would expect evidence for similar behavioral complexity- cave paintings, Neolithic-quality stone tools- in Africa prior to 70,000 years. My guess is that it almost certainly exists, but we just haven't looked in the right places (because it's a lot easier to do fieldwork in Europe than in Africa) or we've found it but haven't recognized it for what it is because the artifacts haven't been dated yet.
Is it less advanced to live in sustainable balance with your environment than to rape and conquer it (and other cultures)?
Let's see how our "advanced" culture looks 75.000 years from now.
What an utterly stupid comment. I've read a lot of dumb comments on slashdot, but ... wow, yours might just be the stupidest thing I've read on the Internet.
First, yes, a culture that never invented writing or the wheel is not advanced, and is markedly less advanced than ones that discovered electricity, writing, forms of societal representation beyond "tribe," compasses, sextants, printing presses, base 10, windmills, aqueducts, gunpowder (I'm trying to pick a wide range of innovations from around the globe here, in case it wasn't obvious) or ones that built pyramids, dams, palaces, walls, houses, etc. I honestly can't see how any remotely rational person would even try to claim otherwise.
Secondly, and what really makes your post stupid, what on earth makes you believe that the Australian aborigines "live[d] in sustainable balance with [their] enviromnent [and didn't] rape and conquered...other cultures"? It's widely believed that aborigines caused the extinction of many species! http://www.cosmosmagazine.com/news/990/aborigines-blamed-big-mammal-extinction! So much for sustainability! Likewise, not only was warfare between aboriginal peoples very common, so was cannibalism.
But really, why let facts stand in the way of your Green Religion that makes being an allegedly noble savage with a small carbon footprint the ideal human life?
I for one am willing to admit that I have not had a successful mating with an Australian.
There's at least some limited evidence of modern behaviors in Africa something around 70,000 years ago. You're a few decades out of date here. In particular see http://en.wikipedia.org/wiki/Klasies_River_Caves
I think timelines are still fuzzy enough to suggest that modern behaviors evolved in Africa itself.
Well surely you need _some_ kind of language to be able to say to a bunch of your friends : "Hey! Fancy going on a beach trip ... to Australia?".
You mean like dogs can mate with wolves and foxes and create perfectly normal offspring? Or the way lions can mate with tigers? I thought at this point the notion that speciesization involved an inability to crossbreed with nearby branches and produced "normal", often fertile, offspring was passe'. Evolution is a lot more interesting than "just Darwin" these days, with the discovery that breeding across species is possible and even commonplace as well as the even more interesting discovery that a significant fraction (maybe 8%) of the human genome is viral DNA probably intercalated via retroviruses in a way that "stuck". It isn't all about simple single-site mutation and in-species crossover anymore (although natural selection itself survives, of course).
However, your point is well taken -- as far as I know the aboriginal genome isn't sufficiently divergent to count as a separate species, any more than the pigmy genome. Or if they are, it's so uber-politically incorrect to point it out that nobody is doing so. OTOH, there was the recent discovery that one single bay in Australia is home to a unique species of porpoise that is genetically divergent enough to be considered separate (although I'd bet it is smoothly crossfertile with other Tursiops).
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Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.