The Polynesian migration got under way about 3000 years ago. However humans have been using boats for longer. That's how Australia was settled about 40,000 yea

The Polynesian migration got under way about 3000 years ago. However humans have been using boats for longer. That's how Australia was settled about 40,000 years ago. I am still cautious about this discovery. The number of archeological sites exploded starting 13,000 years ago, and it coincided with a major set of extinctions. That extinction might not be us, see https://en.wikipedia.org/wiki/Younger_Dryas_impact_hypothesis https://en.wikipedia.org/wiki/Younger_Dryas_impact_hypothesi.... But human arrival in places like Australia is generally associated with major extinctions. So we should expect the same in North America. Early human remains in America have to explain both why they did not leave more remains and why they did not come with a major mass extinction. One possibility is that we were not the only hominids, and 13,000 years ago was not the only time that there was a land bridge across the Bering Strait. What we are is the only primates known to easily cooperate in groups bigger than Dunbar's Number (150 for us). That gives us an outsized impact. If, for instance, the Denisovans had made it to the New World, they could leave convincingly human footprints while having a far lighter ecological impact than we would have.