May 7, 2010

Many people alive today possess some Neanderthal ancestry, according to a new study. The finding has surprised many experts, as previous genetic evidence suggested the Neanderthals made little or no contribution to human inheritance. The result comes from analysis of the Neanderthal genome which indicates that between 1% and 4% of the Eurasian human genome seems derived from Neanderthals. But the study confirms living humans overwhelmingly trace their ancestry to a small population of Africans who later spread out across the world. The most widely-accepted theory of modern human origins - known as Out of Africa - holds that the ancestors of living humans (Homo sapiens) originated in Africa some 200,000 years ago. A relatively small group of people then left the continent to populate the rest of the world between 50,000 and 60,000 years ago. While the Neanderthal genetic contribution - found in people from Europe, Asia and Oceania - appears to be small, this figure is higher than previous genetic analyses have suggested. John Hawks, assistant professor of anthropology at the University of Wisconsin-Madison said of the genetic contribution from Neanderthals, "I am surprised by the amount. I really was not expecting it to be as high as 4%."