The Late Pleistocene was populated by a much larger number of genetically distinct populations than the modern landscape suggests.

Some of these populations survived as the primary ancestors of major modern groups.

Others, like the Ancient North Siberians, contributed components to later populations through admixture without leaving a clearly identifiable modern descendant.

Still others — the Denisovans, the Neanderthals — left genetic contributions in the genomes of modern humans before being absorbed or replaced.

The picture that emerges is of a Pleistocene human world that was densely populated with genetically distinct groups, many of them occupying specific ecological niches and regions, all of them connected through occasional gene flow that linked otherwise distinct lineages.

The far north of Eurasia — precisely the region where Yana sits — was occupied by populations like the Ancient North Siberians who had developed their distinct genetic profile through relative isolation and were then mixing with and being absorbed by other populations as the climate changed and people moved.