There are those from N American tribes who claim they didn’t come from anywhere, that their ancesters were 100% native. Wouldn’t an American origin for the world’s people throw a great big bedpan in a lot of faces? :^) Something amusing to contemplate anyway.
The Americas weren’t peopled in one go, landlubbers should not be writing history books.
I was chatting with a woman in an east coast bar and she said she was from California where she had worked as an archeologist or anthropologist. She and several others had found something human they believed was more than 100,000 years old. I think she may have lost her job over this argument and come east.