Fascinating talk.<br>I'm curious whether the differences in g-factor between different ethnicities could be traced to the migration northwards of some early humans. <br><br>This is just purely speculative thinking based on the information provided in this interview though. I have no horse in this race and no educational knowledge on the subject.,(reply>), @Peter Lund Realised I said some dumb stuff, please ignore me while I dig a hole for myself.,(reply>), We know that IQ can shift quickly if the selection pressure is there… 15 IQ points in a few centuries is possible. Check the breeder’s equation if you are curious.