title: New evidence for the antiquity of man in North America deduced from aspartic acid racemization.
abstract: Ages of several Californzia Paleo-Indlian skeletons have been deduced from the extent of aspartic acid racemization. These dates suggest that man was present in North America at least 50,000 years before the present.
mesh_terms: D000885:Anthropology, Physical; D001224:Aspartic Acid / Q000032:analysis*; D001842:Bone and Bones / Q000032:analysis*; D002140:California; D002250:Carbon Radioisotopes; D002621:Chemistry; D003094:Collagen; D006207:Half-Life; D049690:History, Ancient; D006801:Humans; D007198:Indians, North American / Q000266:history*; D007536:Isomerism; D008334:Mandible / Q000032:analysis; D010163:Paleontology; D012272:Ribs / Q000032:analysis; D012886:Skull / Q000032:analysis
chemical_list: D002250:Carbon Radioisotopes; D001224:Aspartic Acid; D003094:Collagen