I've been hearing lately that the earliest skulls identified as truly Mongoloid anthropologically speaking are only from like 6-8 thousand BC, while proto-Amerindians crossing Beringia into the Americas have been pushed back to at least 15 - 20 thousand years ago. It's true that they are certainly a unique sub-section of that group, but the Siberian-East Asian affinity in indigenous Americans is still pretty clear. What accounts for this time discrepancy then, and how can it be reconciled? I guess they also had a decent amount of ancestry from Ancestral North Eurasians and other more west-Eurasian oriented groups before leaving Asia, so maybe that explains a part of it?