Stone tools, cooked animal and plant remains and fire pits found at the Monte Verde site in southern Chile provide greater interdisciplinary evidence that the earliest known Americans--a nomadic people adapted to a cold, ice-age environment--were established deep in South America more than 15,000 years ago. The research, led by Tom Dillehay, Rebecca Webb Wilson University Distinguished Professor of Anthropology, appears in the Nov. 18 issue of PLOS ONE.