>>11375990population size. If IQ is beneficial, then a large population develops higher IQs than a small one. This is one reason why Americans and Siberians only have an IQ of 90 or so. Of course another reason is just poor environment/bias, because hunters don't exactly spend much time reading or caring about tests.
If there had been some way for Americans to develop a civilized society before getting swarmed by Euros, they would have easily been the highest IQ population in the world, especially the Northern ones. Even moreso than Korea.
I still don't think IQ has ever been beneficial for the last 60,000 years, if not longer. High IQ is just a relic/vestigial structure. It exists because of past pressures that disappeared 60kya. However, high IQ people invent/create better things, and these inventions allow the low IQ populace to invade other territories. Domestication of the dog, cow, horse, etc. all took place outside of Africa.
But these invasions enabled by high IQ inventions are still pale ghosts (pun intended) of the initial fertility-based invasions out of Africa. Dumb fertile people may not be glamorous, but they work, as seen in modern Africa.
