Significance of the "21kya" date: https://en.wikipedia.org/wiki/Peopling_of_the_Americas#Evidence_for_pre-LGM_human_presence https://en.wikipedia.org/wiki/Peop

Significance of the "21kya" date: https://en.wikipedia.org/wiki/Peopling_of_the_Americas#Evidence_for_pre-LGM_human_presence https://en.wikipedia.org/wiki/Peopling_of_the_Americas#Evide... Summary: Recent mainstream theories do not have humans in the America, or at least any further than Alaska, until ~15kya. (1kya = 1 thousand years ago.) However, at a few widely-scattered archaeological sites, there is "debatable" evidence for a much-early human presence. If this new result holds up, it'll be nice new piece of evidence for the "older human presence" camp.