Evolution of modern human beings from nonhuman and extinct hominid forms.
Genetic evidence points to an evolutionary divergence between the lineages of humans and the great apes (Pongidae) on the African continent 5–8 million years ago. The oldest known hominid remains are about 6 million years old. Various fossils dating to at least 4 million years ago are classified as belonging to the genus Australopithecus and are found only in Africa. One of the australopithecines, either A. afarensis or A. africanus , probably gave rise to the species representing the next major evolutionary stage, Homo habilis , which inhabited sub-Saharan Africa until с 1.5 million years ago. H. habilis , in turn, appears to have been supplanted by a taller and more humanlike species, Homo erectus . This species lived from с 2,000,000 to 250,000 years ago and gradually migrated into Asia and parts of Europe. Archaic forms of Homo sapiens with features resembling those of both H. erectus and modern humans appeared с 400,000 years ago in Africa and perhaps parts of Asia, but fully modern humans emerged only 250,000–150,000 years ago, probably having descended from H. erectus .