Hmmm, how does this fit in with the study of Eskimo dentition? From living Eskimos to fossil evidence, there seems to have been 3 different waves, as to teeth types/patterns, that developed in the arctic populations.
I believe Kennewick Man has sundadont teeth.
My understanding is that the linguistic evidence also supports 3 waves. With the Inuit being the most recent. The first wave languages occupied all of South America, central America, and much of North America before European Languages replaced them.