Biology 1001A Chapter Notes - Chapter 21.4-21.5: Homo Erectus, Multiregional Origin Of Modern Humans, Denisovan
Document Summary
The african emergence hypothesis proposes that early hominin decsendants left afrcia and established populations in the middle east, asia, and eurpoe. 100 to 200 hundred thousand years ago, homo sapiens arose in africa and also migrated into europe and asia. Through competition, homo sapiens drove archaic humans to extinction. This suggests that all modern humans are descended form a fairly recent african ancestor. The multiregional hypothesis suggests that populations of homo erectus and archaic humans had spread through much of europe and asia by 500 thousand years ago and modern humans evolved from descendants of these earlier dispersal. Although these geographically separated populations may have experienced some evolutionary differentiation, gene flow between them prevented reproductive isolation and maintained them as a single but variable species. Paleontological data do not clearly support either hypothesis, but genetic data generally supports the african emergence hypothesis.
