DNA Evidence. Aboriginal people of North America have distinct DNA markers from two different Asian cultures that no longer exist in any Asian person alive. This is highly unusual.
In short this means the people of North America are their own people. They are truly North Americans.
Yes I am actually watching this video. Can't sleep. It's very well done but if you want to skip ahead to get to the Canadian/North America part it starts at the 1hour 9 minute mark......