Professor Richard Lynn is a leading authority on the evolution of human intelligence and personality. In a world of social science which ignores evolution, his views are very controversial - see a summary on his website here.
I wrote to Professor Lynn with a "bright idea" I had coming to work a few days ago. I guess he gets a lot of idiotic letters and has refined to high art how he responds.
Dear Professor Lynn,
Most theories of the evolution of costly human intelligence struggle to explain how ancestral human-level intelligence arose on the African savannah in the first place. After all, every other species survives there without it. The argument that ancestral IQ fuelled a "generalist hunter-gatherer strategy” only takes you so far.
Is there a view in the research community that perhaps cold-adaptation drove all of the IQ levels we see today - including within Africa?
ANSWER: No because equatorial Africa never got cold.
The argument is that ancestral proto-humans repeatedly left Africa to the north, encountered differential selection for intelligence and increased cooperation as they encountered tougher ecologies,
and then re-entered Africa displacing the earlier, less intelligent hominids?