Children's teeth reveal previously unknown ancient humans in Siberia

Buried deep in an archaeological site in the north-eastern Siberia taiga, two children’s milk teeth from 31,000 years ago have revealed a new population of humans.

“The genetic record previously suggested that people were only in north-eastern Siberia in the last 10,000 years, but we know from archaeological sites that these populations were there long before that,” says Eske Willerslev at the University of Cambridge in the UK. Archaeological finds told us that people were in this region about 31,000 years ago, but this new genetic data reveals who was there.

They analysed genetic data from 34 samples that range between 31,000 and 600 years old, from high-latitude sites across the Asian continent, from Finland to the Bering Strait. The samples include two fragmented milk teeth from the Yana River site in north-eastern Siberia, which are the oldest human remains found at these harsh northern latitudes.

“The general conception is that the first people getting up there were the ancestors of Native Americans that crossed the Bering Strait and died out,” says Willerslev. “What we see now is that this is by no means how it happened.”

They found a lineage of people in the region that diverged from other populations around 38,000 years ago, which he and his colleagues have named Ancient North Siberians, that were not directly related to Native Americans. “It’s a people we didn’t know about. They died out. They have left tiny traces of DNA in contemporary Siberians but only a small trace, so that was a great surprise,” he says.

Willerslev and his team found that these people moved further south to slightly warmer areas during the Last Glacial Maximum, from about 26,500 to 19,000 years ago. They are genetically closer to the hunter-gatherer populations in western Eurasia that those in the east.

Another sample found near the Kolyma River in north-eastern Siberia dated to 10,000 years old, and may be from a descendant of the Ancient North Siberians. This sample is more closely related to the direct ancestor of Native Americans and to another group that lived east of the Bering Sea, which the team calls Ancient Palaeo-Siberians, who came about when East Asian people mixed with their northern neighbours, says Willerslev.

“It was a really tough environment, but there were still at least three waves of migration,” he says. “Back then, there were large mammals – woolly mammoth, woolly rhinoceros, steppe bison – so in terms of food resources, this was a really attractive place to be. You may be freezing your butt off, but at least you’d have something to eat.”