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## Toward a New Picture of Human Prehistory
The broader context of the Denisova 11 finding is a fundamental revision of how paleoanthropologists understand the late Pleistocene world—the period from roughly 300,000 to 30,000 years ago during which modern humans, Neanderthals, Denisovans, and possibly other archaic groups coexisted, competed, and occasionally interbred.
The older framework, which dominated for much of the twentieth century, imagined this period as one of eventual modern human triumph: a cognitively superior modern human population, equipped with language and advanced symbolic thought, gradually replacing and driving to extinction the archaic groups it encountered. In this framework, Neanderthals and Denisovans were essentially the losing side of an evolutionary competition, their extinction a foregone conclusion once modern humans arrived. The interbreeding evidence complicated this picture, but some researchers initially minimized its significance, arguing that the small percentage of archaic DNA in modern human genomes reflected only very limited and demographically insignificant encounters.
The accumulation of evidence from ancient genomics has made this minimizing interpretation harder to maintain. The Neanderthal DNA in modern humans is present in every non-African population, consistent across continents and populations separated by tens of thousands of years and thousands of kilometers. The Denisovan DNA in Oceanic populations is substantial enough to have contributed meaningful functional adaptations. The evidence of archaic-archaic interbreeding, represented by Denisova 11, establishes that the ancient human world was one in which different groups encountered each other repeatedly and exchanged genetic material.
The emerging picture is more complex, and in important ways more human. Different human groups were not simply competing for space with fixed populations in fixed territories. They moved. They encountered each other. They sometimes reproduced together. The genetic diversity that survives in modern human populations is partly the product of these encounters—a mosaic of ancestry that reflects not the extinction of archaic groups but, in a biological sense, their partial absorption into the lineages that would eventually give rise to all living people.