this is a distinct topic from heritability of iq and race and intelligence since it can also cover prehistory and theories relating to trends in the entire human population
This topic is a nightmare as we have already seen. Many academic sources are from people associated with the group itself; most critical sources are trying to spin their reputation against some unrelated thing they consider evil, especially LGBT, but also occasionally the left, atheism, or academia as a whole, and these sources are often good a disguising their POV on the surface. None the less, this is exactly the reason it’s worth trying to seek out the decent sources amid the cruft.