The Paleoamerican hypothesis, as it had been applied to remains like the Spirit Cave Man and the Kennewick Man, was not supported by the genetic evidence.

The morphological differences between early and late American skulls — the differences that had inspired the hypothesis in the first place — reflected something other than a fundamental genetic discontinuity.

They reflected, as many researchers had argued on non-genetic grounds, the normal variation in skull shape within a founding population that was internally diverse from the beginning, and that changed in measurable ways over time as it adapted to different environments and as genetic drift operated on small, geographically isolated groups.

The earliest well-preserved American genome did not belong to a mysterious, separate founding group.