"For example Sherpas in the Himalayas have evolved to survive in low oxygen air.
Australian aborigines have evolved to survive cold nights in the deserts"
I don't know about that
on the Australian aborigines -- well, I can survive cold nights in deserts ---- I go out in a T shirt down to just a flys fart above zero - quite comfortably -
I wouldn't have done that years ago - but, getting used to being in colder areas and training during the transition periods (now for me) - seems to work well -
so, I doubt if there's been a lot of evolution there barring what we had when we survived the ice age - I might be wrong, but, I don't think so.
Remember - we didn't really evolve to survive the ice age ------ what we did was - we invented the needle.
""For example Sherpas in the Himalayas have evolved to survive in low oxygen air."
hmmm - yes, possibly with one generation to the next - but, I would have thought that any healthy child who grew up at higher altitudes would survive and thrive in the lower oxygen air.
Edmund Hilary wasn't a Sherpa - and, by god - he got to the top -
that's 8,849 m --------- my guess is that he was a NZ kid who spent a lot of time up things - and, his body got used to it.
I spent some time at a mere 2,500 m a few weeks back and thought I was ready for death - my god, that was uncomfortable -
but, I reckon if I work at it - even now - way beyond being a kid - if I work it up at about 1500 for a while - then, a trip to 2,500 m would not be like my first trip was
half of the bloody planet has climbed Everest and a heap of Kiwis go up big rocky things all the time --- so - I'm not sold on that we evolved there - more than we did - hundreds of thousands of years back
I am rolling here on feeling - not on research - so, I won't stand fixed on any of it - but, it all seems to make sense to me.
oh - I agree on genetic variation ----------- inside our own populations as well
