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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 ... '"
It is believed that at one point the population of the human race was knocked down to a few thousand. This is backed up with genetic testing. Humans are extremely similar in terms of genetics. There is more difference between two random humans in the same race, then there is between two average humans of different races. In other words, if were to average all the genetics of each individual race, you would find that they are more similar to each other then difference you find between humans due to natural variation. It is pretty conclusive that humans all descend from the same few thousand people.
The "Eve" theory is evidenced by mitochondrial DNA.
We are all related to some nice lady from about 150,000 years ago. that's EVERYONE, mind you.
DNA doesn't lie. Modern homosapiens are all from the same place.
The problem has always been that there are two sorts of strong evidence: humans are almost all alike, and humans evolved in place. (E.g. early Australians were H. erectus; later they had mixed erectus and sap. characteristics; eventually the erectus features faded and vanished, leaving pure H. sap.) Naturally each had adherents who preferred to discount the others' evidence. The two have certainly seemed contradictory, up until now.
They were both right. What spread out of Africa was not actual populations of H. sap. etc., supplanting H. erectus populations that preceded them. Rather, successful gene complexes that define H. sap. spread out of Africa, upgrading local populations in-place. (Think of them as software patches.) Hardly anybody had to migrate any farther than the next village over. People married into neighboring villages, bringing their genetic advances with them, and the next generation brought them to the next village along. Of course successful genes could spread back to Africa, too, but Africa had the most variation, so produced more of the successful genes, and packaged them with more other, complementary genes.
Contrast this with the spread of agriculture into Europe, where there's evidence of farmers actually supplanting hunter/gatherers; and of course the historical record, with wholesale slaughters and genocides. (No doubt there was plenty of slaughtering earlier, but it takes technology, language, and civilized infantilization for genocides to be conducted efficiently.)
It doesn't seem like there are many other species in which this process would have worked. Bears, maybe.