SO, WHEN DID PEOPLE ARRIVE IN THE WEST?

With the acceptance of Monte Verde the presence of people in the Americas prior to 12,000 rcy B.P. can no longer be denied. But, where might we look for evidence of those earlier occupations? Could areas in the Intermontane West, such as the Great Basin, for example, have supported colonizing populations between 20,000 and 25,000 rcy B.P.? The earliest evidence in this region, as is the case elsewhere in the Intermontane West, is no earlier than 12,000 rcy B.P., although there are several earlier radiocarbon dates that are debated. Further, the earliest archaeological evidence occurs almost exclusively in lowland situations, largely near shrinking Pleistocene lakes, in what would have been wetland contexts. But these habitats did not develop until about 13,000 rcy B.P., after lakes had receded from their high stands. If people entering this region were already adapted to wetland resources, then they probably did not arrive much earlier than 12,000 rcy B.P. If, on the other hand, they arrived earlier, was resource productivity sufficient to support them? We examine the changing environments of the Intermontane West from 25,000 to 12,000 rcy B.P. and evalute the probability that pwople arrived in this region before widespread evidence appears. We discuss the extant radiocarbon record for pre-12,000 rcy B.P. occupations as well as intriguing new evidence provided by obsidian hydration dating.