He was a European with dark skin and dark eyes. And his ancestry was mixed. A group of geneticists have sequenced DNA from the remains of a man who died 36,000 years ago in Kostenki, Russia, near the Ukraine border. The results are surprising, and could reveal a lot about how modern humans spread out of Africa.
Reconstruction of Kostenki XIV (Markina Gora), by M. M. Gerasimov
What's most intriguing about this man, nicknamed Markina Gora, is that his genome suggests that he was of mixed ancestry, showing traces of many different groups who lived in Europe, including Middle Eastern, Western Asian and Neanderthal. In fact, his DNA looks a lot like a contemporary European's. This detail is important because other research has suggested that European groups wouldn't have had such a mixed genetic heritage until roughly 5,000 years ago.
Essentially, what we're learning is that Europeans have never really been an isolated population — they are the result of very early connections forged between the groups who eventually settled in the Middle East and Western Asia. This offers us a slightly different picture of early Europe, and suggests that humans spreading out of Africa didn't separate into segregated groups. Instead, they were having children together — at least in regions where the different populations overlapped — and sharing their genetic diversity.
From the sequence data, they found gene variants indicating that the man had dark skin and eyes. He also had about 1% more Neandertal DNA than do Europeans and Asians today, confirming what another, even older human from Siberia had shown—that humans and Neandertals mixed early, before 45,000 years ago, perhaps in the Middle East.
The man from Kostenki shared close ancestry with hunter-gatherers in Europe—as well as with the early farmers, suggesting that his ancestors interbred with members of the same Middle Eastern population who later turned into farmers and came to Europe themselves. Finally, he also carried the signature of western Asians ...
Willerslev says the data suggest the following scenario: After modern humans spread out of Africa about 60,000 years ago, they encountered Neandertals and interbred with them, perhaps in the Middle East. Then while one branch headed east toward Melanesia and Australia, another branch of this founder population (sometimes called "basal Eurasians") spread north and west into Europe and central Asia. "There was a really large met-population that probably stretched all the way from the Middle East into Europe and into Eurasia," [evolutionary biologist Eske] Willerslev says. These people interbred at the edges of their separate populations, keeping the entire complex network interconnected—and so giving the ancient Kostenki man genes from three different groups. "In principle, you just have sex with your neighbor and they have it with their next neighbor—you don't need to have these armies of people moving around to spread the genes."
Later, this large population was pushed back toward Europe as later waves of settlers, such as the ancestors of the Han Chinese, moved into eastern Asia. The Kostenki man does not share DNA with eastern Asians, who gave rise to Paleoindians in the Americas.
Willerslev also noted that this means the "pure European" lineage goes back at least 36,000 years. And by "pure," he means mixed.
Read more in Science.