May 23, 2010
from YouTube Website
Scientists have estimated that humans branched off from their common ancestor with chimpanzees - the only other living hominins - about 57 million years ago. Several species of Homo evolved and are now extinct.
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 H. sapiens arose in Africa and migrated out of the continent around 50,000 to 100,000 years ago, replacing populations of H. erectus in Asia and H. neanderthalensis in Europe.
Scientists supporting the alternative multiregional hypothesis argue that H. sapiens evolved as geographically separate but interbreeding populations stemming from a worldwide migration of H. erectus out of Africa nearly 2.5 million years ago.