Friday, May 7, 2010

Neanderthals live on

Most People Carry Neanderthal Genes
WSJ: The burly Ice Age hunters known as Neanderthals... survive today in the genes of almost everyone outside Africa, according to an international research team who offer the first molecular evidence that early humans mated and produced children in liaisons with Neanderthals...

The researchers mapped most of the Neanderthal genome [and] found the Neanderthal legacy accounts for up to 4% of the human genome among people in much of the world today...

The Neanderthals, a big-brained and barrel-chested group... roamed Europe, Russia and the Middle East between 400,000 years and 30,000 years ago, overlapping in many areas with the direct ancestors of modern humankind. Their remains were the first human-like fossils ever found...

In research published in Science, the researchers compared the Neanderthal DNA to the genomes drawn from five people from around the world: a San tribesman from South Africa; a Yoruba from West Africa; a Han Chinese; a West European; and a Pacific Islander from Papua, New Guinea... Traces of Neanderthal heredity turned up in all but the two African representatives...

From that pattern, the researchers deduced that prehistoric humans encountered their Neanderthal mates in the Middle East as small human bands first migrated out of their African homeland...

Based on these findings, several anthropologists questioned whether Neanderthals should continue to be considered a separate species. Typically, when different species mate, they don't produce fertile offspring...

The new research is buttressed by an independent, unpublished survey of modern human diversity, involving DNA markers covering 100 population groups world-wide, which also offers evidence of ancient inbreeding between Homo sapiens and earlier archaic human species.

Huffington Post: Todd Disotell, an anthropologist at New York University, suggested that more Africans should be sampled... He noted that the researchers looked at the genomes of a west African and a south African, but not someone from northeast Africa, where he said the mixture would be more likely to have occurred...

[Population geneticist David] Reich noted that while there was a flow of genes from Neanderthals to modern humans, there is no indication of gene movement the other way, from humans to Neanderthals...

While many people think of Neanderthals as very primitive, they had tools for... hunting and sewing, controlled fire, lived in shelters and buried their dead.
Image: Vindija cave in Croatia, source of DNA from remains of three women who lived between 38,000 and 45,000 years ago.