Tag: Out of African

The paradigm is dead, long live the paradigm!

By Razib Khan | December 23, 2010 3:24 am

Mitochondrial DNA and human evolution:

Mitochondrial DNA from 147 people, drawn from five geographic populations have been analysed by restriction mapping. All these mitochondrial DMAs stem from one woman who is postulated to have lived ab7out 200,000 years ago, probably in Africa. All the populations examined except the African population have multiple origins, implying that each area was colonised repeatedly

And so was published in the year 1987 the paper which established in the public’s mind the idea of mitochondrial Eve, which gave rise to a famous cover photo in Newsweek. This also led to the Children of Eve episode on the PBS documentary NOVA. Here is the summary:

NOVA examines a controversial theory that traces our ancestry to a small group of women living in Africa 300,000 years ago.


As Milford Wolpoff has complained it is probably accurate to characterize the documentary as not particularly “fair & balanced.” Mitochondrial Eve may have been controversial, and subsequently plagued by issues of molecular clock calibration as well as spurious interpretations of the cladograms, but the tide of history was on its side, and PBS was telling that story. And the story was not just the primary science, rather, one had to understand the controversy in light of the debates among paleontologists and between paleontologists and molecular biologists. A group of researchers, spearheaded by Chris Stringer argued for the recent origin of modern humans from Africa on the basis of fossils alone. They were challenged by an established school of multiregionalists who argued for deeper roots of modern human populations, which derived from local hominins which diversified after the the migration of H. erectus out of Africa. The argument of the multiregionalists was that selective sweeps across the full range of the human populations gave rise gradually to modern humanity as we know it, a compound of specific ancient local features and trans-population characters which unified us into a broader whole. Stringer and company presented a simpler model where anatomically modern human being arose ~200,000 years ago in Africa, and subsequently expanded to other parts of the world, by and large replacing the local hominin populations. In the multiregionalist telling Neandertals became human beings, while Out of Africa would imply that Neandertals were replaced by human beings.

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Which population is most genetically distant from Africans?

By Razib Khan | August 18, 2010 1:58 pm

A comment below:

Razib, I don’t know much about genetics but is it true that these people of Melanesia are among the least related people (even more so than Europeans) to sub-saharan Africans genetically??

This is a common question. The typical scientifically curious intelligent person is generally aware that on the order of 100,000 years ago there was a movement of anatomically modern humans from Africa. They know that Africans have the most genetic variation of any human population, and that in fact Africa has more genetic variation than the rest of the world combined. It would stand to reason then that the further you are from Africa, the more genetically distant you are. Simply because of recent admixture of Sub-Saharan African ancestry in much of the Middle East there is some truth to this, but I think it misses the “big picture.”

To the best of my knowledge the current consensus on the origin and expansion of modern humans goes like so:

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CATEGORIZED UNDER: Evolution, Genetics, Genomics
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