Posted on 03/06/2002 7:38:41 PM PST by ValerieUSA
Explains my boss perfectly.
Early man evolved by spreading love, not war
By Steve Connor, Science Editor
07 March 2002
The came, they saw and they made love, not war. This is the story of how our human ancestors spread across the world, according to the most detailed study of our genetic heritage attempted so far.
Alan Templeton, professor of biology at Washington University in St Louis, Missouri, has found convincing evidence to suggest that the history of human evolution is one of sexual interchange rather than the physical elimination of one group by another.
"Humans expanded again and again out of Africa, but these expansions resulted in interbreeding, not replacement, and thereby strengthened the genetic ties between human populations throughout the world," he said.
The study, a computer analysis of the DNA from people living in 10 different regions of the world, was more extensive than any previous research, Professor Templeton said.
The findings, published today in the journal Nature, add a new twist to the long-running dispute over whether modern humans are the result of a single migration out of Africa some 100,000 years ago, or the product of a series of migrations extending back over one million years to several regional homelands in Asia as well as Africa.
"The main conclusions are that human populations in Africa and Eurasia have not been genetically isolated from one another, but rather have been interchanging genes for least 600,000 years," Professor Templeton said.
"This 'gene flow' was restricted, primarily by geographical distance, which meant that local populations could and should show genetic differences, as they do today. But over a long time there was sufficient genetic interchange to insure that all humanity evolved as a single species."
Professor Templeton's research indicates that there were two important waves of migration out of Africa one about 600,000 years ago when humans were represented by "archaic" species such as Homo heidelbergensis and the Neanderthals, and the other about 95,000 years ago, soon after the rise of anatomically modern Homo sapiens.
Professor Templeton said the earlier migration coincided with a significant expansion in brain size and the latter with the appearance of "modern" traits, such as smaller brow ridges, a rounded skull, a vertical forehead and a pronounced chin.
"This later set of traits is difficult to reconcile with a population replacement, but is compatible with this most recent out-of-Africa expansion event being characterised by interbreeding," he said.
Eight of the 10 DNA regions Professor Templeton studied possessed characteristics that dated back well before 100,000 years ago, meaning that they predated the migration of Homo sapiens. Those features could only be accounted for by interbreeding between the newly arrived migrants and the resident Asian population, he said.
Professor Chris Stringer, a palaeontologist at the Natural History Museum in London and a prime proponent of the "replacement" theory, said Professor Templeton's study was interesting but needed to be scrutinised by geneticists who had come to different conclusions, albeit based on smaller samples of DNA.
(I agree with Professor Templeton)
Sounds like saplings for new branches of ethnic slurs.
What is the product of a crooked disbarred lawyer mating with a corrupt politician?
Answer: Chelsea.
BWAHAHAHA James Carville.
...and thence, on to San Francisco. ;-)
Jeans, hmmm... maybe baggy jeans - definitely not well-fitted skirts.
If you dropped the Chinese off in the Midwest, they would claim the same thing.
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