Global Expansion 300 000–8000 Years Ago, Americas

Abstract

Exactly when humans first entered the American Continent, and from where, is still a matter of heated discussion by scientists today. Several migration routes have been proposed to reach the Americas, involving the use of the Bering Land Bridge from Siberia to Alaska or the use of watercraft along the Pacific or Atlantic Coasts; part of the current research involves trying to put times into the potential migration routes into the Americas. Also the role of the arrival of humans in the extinction of megafauna (mammoths, saber-toothed cats, camels, horses, etc.) is discussed against the effect of environmental changes at the end of Pleistocene (~10000 years ago). Strong archeological evidence suggests that humans arrived in the Americas long before 12000 RCYBP and that the Clovis people were not the first group to migrate into the New World. New information derived from linguistics, stone tools, craniometrics, and genetic evidence strongly suggests that the first Americans were very diverse from an ethnic point of view. However, the study of many more early human skeletons is required to construct a real picture.