Race and Genetics - Human Evolution

Human Evolution

The human lineage diverged from the common ancestor with chimpanzees about 5–7 million years ago. The genus Homo evolved by about 2.3 to 2.4 million years ago from Australopithecines. Several species and subspecies of Homo evolved and are now extinct. These include Homo erectus, which inhabited Asia, and Homo sapiens neanderthalensis, which inhabited West Eurasia. Archaic Homo sapiens evolved between 400,000 and 250,000 years ago.

The dominant view among scientists concerning the origin of anatomically modern humans is the "Out of Africa" or recent African origin hypothesis, which argues that Homo sapiens arose in Africa and migrated out of the continent around 50,000 to 100,000 years ago, replacing populations of Homo erectus in Asia and Homo neanderthalensis in Europe. This theory has largely displaced an alternative multiregional hypothesis which argues that Homo sapiens evolved as geographically separate but interbreeding populations stemming from a worldwide migration of Homo erectus out of Africa nearly 2.5 million years ago. Although scientists have generally replaced Homo erectus with Homo sapiens as the favored common ancestor of modern humans, it has recently been shown with DNA evidence that non Homo sapiens Neanderthal genomes may have contributed about 4% of non-African heredity, and the recently discovered Denisova hominin may have contributed 6% of the genome of Melanesians.