Humans aren’t particularly genetically diverse, given our dispersal, though as far as I know there’s some disagreement on _why_.
That's absolutely correct. One set of hypotheses about this are population bottleneck theories[0].
As an example, the Toba Catastrophe Theory[1] posits that:
"The Youngest Toba eruption has been linked to a genetic bottleneck in human evolution about 70,000 years ago,[28][29] which may have resulted from a severe reduction in the size of the total human population due to the effects of the eruption on the global climate.[30] According to the genetic bottleneck theory, between 50,000 and 100,000 years ago, human populations sharply decreased to 3,000–10,000 surviving individuals.[31][32] It is supported by some genetic evidence suggesting that today's humans are descended from a very small population of between 1,000 and 10,000 breeding pairs that existed about 70,000 years ago.[33][34]"
Whether such theories are correct or not, they appear to fit with the lack of genetic diversity among humans.
I'd have assumed that it's largely because humans can spread to new niches via cultural evolution, which happens vastly faster than the old-fashioned biological kind. Much quicker to make a fur coat than evolve one.
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Humans aren’t particularly genetically diverse, given our dispersal, though as far as I know there’s some disagreement on _why_.
That's absolutely correct. One set of hypotheses about this are population bottleneck theories[0].
As an example, the Toba Catastrophe Theory[1] posits that:
"The Youngest Toba eruption has been linked to a genetic bottleneck in human evolution about 70,000 years ago,[28][29] which may have resulted from a severe reduction in the size of the total human population due to the effects of the eruption on the global climate.[30] According to the genetic bottleneck theory, between 50,000 and 100,000 years ago, human populations sharply decreased to 3,000–10,000 surviving individuals.[31][32] It is supported by some genetic evidence suggesting that today's humans are descended from a very small population of between 1,000 and 10,000 breeding pairs that existed about 70,000 years ago.[33][34]"
Whether such theories are correct or not, they appear to fit with the lack of genetic diversity among humans.
[0] https://en.wikipedia.org/wiki/Population_bottleneck
[1] https://en.wikipedia.org/wiki/Toba_catastrophe_theory#Geneti...
I'd have assumed that it's largely because humans can spread to new niches via cultural evolution, which happens vastly faster than the old-fashioned biological kind. Much quicker to make a fur coat than evolve one.