And the “scientists” assume that all the genetic differences between the samples are due to climate-change driven evolution.
There could be nothing else????
I don’t know where to begin tearing this down. (You can’t pick up the clean end of a turd.)
Climate change is the rule rather than the exception. It is constantly changing regionally even while remaining generally stable globally. Genetic drift is one of the big movers of evolution. A population has many individual differences, some of which may be beneficial in a dry climate to the extent that more individuals with that variation survive and reproduce during a drought. The population as a whole will drift in that direction.
We’ve got climate change over short or long periods of time regionally in many parts of the world. Desertification in East Africa had its influence on human evolution.