[Maursault]

> but nothing like periods where everything collapses globally.

What else but a population bottleneck could explain the lack of any genetic diversity to speak of in humans? No human alive today is more distantly related to you than 37th cousin. Any two random individuals are 99.9% identical. That's weird. For this to have occurred, something must have happened everywhere all at once.[1]

[1] https://https://en.wikipedia.org/wiki/Toba_catastrophe_theor...

[ummonk]

Yeah I don't disagree, which was why I caveated it by saying "since the end of the last glacial period".

Before that, all bets are off, and I personally do consider the Toba catastrophe a possible explanation for the ridiculously low level of genetic diversity in modern humans outside sub-Saharan Africa.

[svnt]

Not necessarily — it could just as easily have been a founder population event, combined with “weird” sexual selection.

[Maursault]

I like this idea. A long time ago, there was one amazingly attractive, irresistibly seductive, incredibly promiscuous and astoundingly prolific breeding individual and sexual athlete: the legendary Don Juan of the late Pleistocene.