The common explanation of the ME is that the human population faced a bottleneck sometime in the past.
No, not really. There
was a bottleneck, but that isn't why ME existed.
That's just inevitable. Humans are one species, everyone has a mother, and no-one has more than one mother. Given these facts, one can prove the
existence of ME from one's armchair.
People often get confused about this. The fact that ME
existed was not news. It was inevitable. The date and location at which she existed was news.
If I was one of those scientists I'd have gotten downright testy about that.