This was another surprise.

The people of ancient Siberia, who in the popular imagination might be seen as isolated and distinct from the populations of Europe and the Middle East, turned out to be genetically connected to the ancestry of modern Western Eurasians in ways that the pre-2013 understanding had not clearly recognized.

This connection reflects the complex population history of Eurasia during and after the last glacial period.

The populations that eventually gave rise to modern Europeans were not simply the descendants of the people who inhabited Europe during the Upper Paleolithic — they also incorporated ancestry from populations that had lived further east, including populations ancestral or related to the Ancient North Eurasians of Siberia.