The Denisovan contribution to modern populations is more concentrated geographically, but it too has identifiable functional effects.

The most striking is the contribution of a gene called EPAS1 — a variant found in Tibetan populations that allows them to live and work at high altitudes without the physiological challenges that high altitude poses for most modern humans.

This Denisovan-derived EPAS1 variant appears to have been adaptive for populations moving into the high-altitude environments of Tibet and the Himalayas — environments where Denisovans may have lived for tens or hundreds of thousands of years, developing adaptations that modern humans inherited through interbreeding.

The Denisovan EPAS1 is one of the clearest examples of adaptive introgression — the transfer of a beneficial genetic variant from one species to another through interbreeding.