The most securely dated and most widely accepted pre-Clovis site is Monte Verde in southern Chile, where direct radiocarbon dates on organic materials associated with human artifacts have consistently produced ages of approximately 14,500 calibrated years before present.

The significance of this date is amplified by Monte Verde’s geographic location — at the southern tip of South America, far from any proposed point of entry into the Americas.

For people to have been at Monte Verde 14,500 years ago, they must have entered the Americas considerably earlier, requiring enough time for a human population to disperse from the entry point in Beringia to the southern end of South America.

Cooper’s Ferry in Idaho has produced lithic artifacts from a context that has been dated to approximately 15,000 years before present — older than Paisley, and farther north, closer to the proposed entry point.