It’s nonsense. And those videos are beyond nonsense. They’re fun. They’re a mythology. But it’s total nonsense.
OUT OF AFRICA AND BACK AND FORTH
There was back and forth gene flow. There was back and forth gene flow between previous generations of man. But the what’s called ‘the whole kit’ emerged in east africa, spread across into then-green saudi peninsula, but settled in the then-dry persian gulf and it’s many rivers and marshes – the optimum ground for mankind. And then spread out following the coastal route. Because once you have fishing you’re never going to starve. Conversely, if you migrate for large game up the rivers whether the Tigris and Euphrates or the Indus, you will find game that has no experience with humans and the returns on that game, especially given the furs, skins, and bones, were better than those of the fish in the sea. So yes there has always been back and forth gene flow, and yes some of the backward gene flow was contributory because it’s easier to isolate and speciate outside of africa than in it – if you have the ‘full kit’ of technologies necessary to survive in numbers outside of africa.
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