We know people in southeast Asia 70,000 years ago had boats they deliberately sailed out of sight of land: they colonized Australia. (Maybe via Timor, maybe Sul

We know people in southeast Asia 70,000 years ago had boats they deliberately sailed out of sight of land: they colonized Australia. (Maybe via Timor, maybe Sulawesi, maybe both.) That they would have sailed wherever else they could, including along the Aleutians to North America, is the null hypothesis: you would need to demonstrate that they didn't, and show why not. The region had a million square miles of bottom land now under the sea. People lived there for tens of millennia, and were driven by sea level rise, generation by generation, to high ground where other people already lived. Something dramatic happened much more recently such that much of the population of the region now traces ancestry to a mother population from Taiwan. Plague, maybe? Another puzzle.