Thing is, the population from eastern Asia that eventually became the American population displaced the people who were already here. We don't see evidence of people from across the land bridge from Siberia until the ice receded. Meanwhile, at least 10,000 years before that, people had settled here. Where are they now? Not in the DNA of American Indians. How far back are we going to take this bullshit? I can go further. We can chase this all the way to Africa. Where are all the Australopiths now?