Human evolution
H. sapiens

H. sapiens (the adjective sapiens is Latin for "wise" or "intelligent") emerged in Africa around 300,000 years ago, likely derived from H. heidelbergensis or a related lineage. In September 2019, scientists reported the computerized determination, based on 260 CT scans, of a virtual skull shape of the last common human ancestor to modern humans (H. sapiens), representative of the earliest modern humans, and suggested that modern humans arose between 260,000 and 350,000 years ago through a merging of populations in East and South Africa.

Between 400,000 years ago and the second interglacial period in the Middle Pleistocene, around 250,000 years ago, the trend in intra-cranial volume expansion and the elaboration of stone tool technologies developed, providing evidence for a transition from H. erectus to H. sapiens. The direct evidence suggests there was a migration of H. erectus out of Africa, then a further speciation of H. sapiens from H. erectus in Africa. A subsequent migration (both within and out of Africa) eventually replaced the earlier dispersed H. erectus. This migration and origin theory is usually referred to as the "recent single-origin hypothesis" or "out of Africa" theory. H. sapiens interbred with archaic humans both in Africa and in Eurasia, in Eurasia notably with Neanderthals and Denisovans.

The Toba catastrophe theory, which postulates a population bottleneck for H. sapiens about 70,000 years ago, was controversial from its first proposal in the 1990s and by the 2010s had very little support. Distinctive human genetic variability has arisen as the result of the founder effect, by archaic admixture and by recent evolutionary pressures.
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