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Humans First Arose in Asia?
IZ Reloaded writes "Two archaeologists are proposing the idea that early humans first arose in Asia instead of Africa as previously thought. These early humans then migrate out of Asia to parts of the world. From National Geographic: 'The unresolved status of the intriguing Flores finds attributed to H. floresiensis leaves open the possibility that this species is the end result and last survivor of an ancient migration of very primitive humans, or even prehumans, that formerly existed more widely across Asia ... '"
Actually, it seems like they're proposing that humans (or, rather, their ancestors) migrated from Asia to Africa *before* what we already know about, so the two theories don't rule each other out. It all just depends on where you draw the line between "human" and "not quite human yet".
quidquid latine dictum sit altum videtur.
Actually, after having RTFA, the article is somewhat sensationalised.
First, they do not doubt that H. erectus came out of Africa, it's very well established that it did. The issue with that, is that H. sapiens are believed to have had H. erectus as ancestors. So "humans" in so far as it means H. sapiens, came from Africa to the best possible explaination that anyone has.
The issue here is that they're discussing where other hominids came from, and where the hominids that evolved in Africa came from.
If they did mean Asia, then it would mean somewhere near the modern country of Georgia, not far east Asia, or middle east Asia. Just plain "Asia" (it's pretty easy to forget that many Russians are Asians, not Europeans)
Since they know those areas of Asia to have been covered with similar Savannahs as Africa during about 1.8 some million years ago, they say that you can't rule out that early hominids could have been thriving in that area, or that hominids didn't actually come from that area, and just had an early migration into Africa.
They point to H. floresiensis, saying that it was likely a terminating evolutionary point of an orphaned hominid line independent of African evolutionary heritage.
I am unamerican, and proud of it!
"I'm not debating their points (I've not read the article yet), but it would seem to require us to throw out the data that we already have."
No, it doesn't.
It just asks us to start looking in Asia also. "All the evidence" comes from Africa because all the digs are happening in Africa. Archaeology and paleontology are sciences which suffer from heavy biases in their observations. First off, what are the chances that any bone would become a fossil? Slim to none. Secondly, we can't ramdonly sample the whole earth's surface with dig teams. We dig in places where the lead researcher "has a good feeling", or gets word from a local farmer about strange rocks.
"If homo species migrated to the rest of the world from Asia, then it would have requires Lucy, a relatively primitive human to have gotten to Africa, then start a long series of descendents and multiple branches of evolution there, eventually resulting in homo sapiens."
Lucy, who was an Australopithecus afarensis (way before people -- not even Homo or same as us ) stays in Africa, as does her descendants, A. garhi.
Her even later descendents Homo erectus, H. habilis, or neanderthalis wanders out into Asia and becomes H. sapiens, who in turn wanders back to Africa, and of course, the rest of the world. Note that fossils of H. erectus, which is considered to be two species before modern humans, were found in Dragonbone cave in China.
A good understanding of this wikipedia entry for human evolution might help you understand the situation.
Computers are useless. They can only give you answers.
-- Pablo Picasso
That wasn't a snake. It was the Noodly Appendage of the Flying Spaghetti Monster. (The rest of the FSM was hiding further up the tree.) Oh, and it wasn't an apple that was offered to Eve - it was a tomato.
--Ender
Loose things are easy to lose. You're getting your hair cut. They're going there to see their aunt.
The article talks quite a bit about fossil evidence, but what about the genetic evidence? If you look at the variability of human genetics, you find that europeans aren't very genetically diverse. Similarly, American Indians aren't very genetically diverse, and Asians aren't either. Africans, on the other hand, are very genetically diverse. What this indicates is that the human race' history in Africa goes back much further than anywhere else. It appears that a subset of Africans left Africa and colonized the rest of the world. Here's a short article that talks about human genetic diversity compared to their location: http://info.med.yale.edu/genetics/kkidd/point.html
http://www.umich.edu/news/?Releases/2005/Oct05/r10 1805
It seems like you're paraphrasing (badly) Pascal's Wager. Google it.
Trolling is a art,
It's trickier than that. It's highly unlikely that there was only one woman. (Your post doesn't explicitly make that claim, but a lot of people misunderstand the subject to mean that.) It's possible for there to have been lots and lots of women, but because mitochondria are only passed from women to children, and because roughly half the kids are boys, it's possible to have, over a fifteen or twenty generation sequence, only one woman's mitochondria passed through. I'm working from "Patterns In Evolution" by Roger Lewin here, and, as a demo, he posits 16 couples, each of whom have two children, and tracking those through 15 generations.
"At each generation, one quarter of the mothers will have two male offspring, one quarter will have two females, and one half will have one of each. The mitochondrial lineages of mothers that have only males will come to an end and eventually one lineage will dominate the entire population."
In other words, the Eve hypothesis shows the region of origin of modern humanity, which is pretty clearly Africa, and tells us roughly when, assuming mitochondrial DNA information drift is relatively constant. It does not require a big population bottleneck. People probably assumed a bottleneck from an incomplete understanding of genetics and a certain wish to have a correlation with a well-known story (in the West) about a single mother of all humans.
The dude who did the original research, Alan Wilson, estimated there were probably over 10,000 women in the breeding community that contained the ancestral Eve. Other critics of the theory say you can't even make THAT claim.
Nostalgia's not what it used to be.