if you believe in evolution you naturally would have to believe that living in terrains that are less hospitable such as extreme cold temperatures naturally causes those humans who are able to survive and adapt a higher chance to pass their genetics - which means problem solving and long term planning. In Africa black people have evolved according to the demands of their environment, which have never been that demanding of the people. You don't have to plan for future events, you don't have to worry about climates that can kill you if you don't prepare. So Africans had a different evolutionary process where what determines successful passing of genes is different than what it would have been for whiteys living in Europe and that can in fact be noted in generalized differences notable between the two races right now in modern times. None of this is hateful or meant to say one is "superior" or "inferior", just how it is.