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0 pointsaz09mugen7mo ago0 comments

I was wondering the same question, and IIRC it's due to the DNA diversity we have today. This is roughly calculated with the successive generations of humans and accounting possible mutations.

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squigz7mo ago· 1 in thread

If this is the case, how can we know whether that number represents a drop in population or not? Can we measure population size 100,000 years ago? 50,000? Then compare them? What about that number represented as % of total population? 1,000-10,000 sounds low, but our population probably wasn't very high that long ago either.

recursivecaveat7mo ago

Hypothetically if you took a random sample of present humans you would have a low # of say skin tones in wide range, whereas a small isolated and stable population should have a low # of low variety. So you can tell by that kind of difference whether it was a sudden drop or more of a sustained thing. Presumably in a more sophisticated statistical way across a wide variety of genes of course.

Apparently there is another bottleneck ~900K years ago that has decent fossil record support but the Toba one is more disputed.

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