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NORTH 02 | Ancient Human | Denisovan

The Denisovans or Denisova hominins are an extinct species or subspecies of archaic human that ranged across Asia during the Lower and Middle Paleolithic.

Denisovans are known from few physical remains and consequently, most of what is known about them comes from DNA evidence. No formal species name has been established pending more complete fossil material.


The first identification of a Denisovan individual occurred in 2010, based on mitochondrial DNA (mtDNA) extracted from a juvenile female finger bone excavated from the Siberian Denisova Cave in the Altai Mountains in 2008.[1] Nuclear DNA indicates close affinities with Neanderthals.


The cave was also periodically inhabited by Neanderthals, but it is unclear whether Neanderthals and Denisovans ever cohabited in the cave. Additional specimens from Denisova Cave were subsequently identified, as was a single specimen from the Baishiya Karst Cave on the Tibetan Plateau, and Cobra Cave in the Annamite Mountains of Laos. DNA evidence suggests they had dark skin, eyes, and hair, and had a Neanderthal-like build and facial features. However, they had larger molars which are reminiscent of Middle to Late Pleistocene archaic humans and australopithecines.


Denisovans apparently interbred with modern humans, with the highest percentages (roughly 5%) occurring in Melanesians, Aboriginal Australians, and Filipino Negritos. This distribution suggests that there were Denisovan populations across Eurasia, the Philippines, and New Guinea and/or Australia, but this is unconfirmable. Introgression into modern humans may have occurred as recently as 30,000 years ago in New Guinea, which, if correct, might indicate this population persisted as late as 14,500 years ago.


There is also evidence of interbreeding with the Altai Neanderthal population, with about 17% of the Denisovan genome from Denisova Cave deriving from them. A first-generation hybrid nicknamed "Denny" was discovered with a Denisovan father and a Neanderthal mother.


Additionally, 4% of the Denisovan genome comes from an unknown archaic human species which diverged from modern humans over one million years ago.


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