Human brains are modern by 40KYA From acheological and cultural remains we know that the human brain has evolved to its modern cognitive powers by 40KYA Some recent achaeological studies have pushed that to an even earlier date evidence in Zaire etc Hence 40KYA is also refered to as the Great Leap Forward by Jared Diamond in his book Guns Germs and Steel Hence it follows that the reason why Africans do poorly while Eurasians did so well has nothing to do with IQ they all have the same IQ but rather to do with geography Those people that happen to live near fertile places with many animals for domestication get to start farming and agriculture which beings about societal differentiation sohistication and size However anatomically humans have reached the modern state by 200KYA from studies of OMO1 OMO2 and Herto in Ethiopia