IQ tests are recent and evolution doesn't work that fast.
Well, see, that's what we used to think. While evolution still may and does move very slowly in cases, its also may happen very quickly over just a few generations, due to experiences, not the normal drivers of evolution. We used to dismiss this as LaMarckian. But epigenetics has thrown biology for a loop.
Appearance of language and arithmetic may have been watershed moments that brought such wpigenetic pressure on our brains. The sientific enlightenment may he another. Still another: cities.
I say maybe, which also means, maybe not.
One quirky thing about epogenetics: convergence. Two isolated populations would presumably respond similarly to an epigenetic pressure. It would be an interesting experiment to test this with isolated, aboroginal tribes.