as Africans and black races emigrated throughout the world they evolved and through natural selection we ended up with white people in the northern hemisphere, Those that stayed behind in the African continent stayed the same and didn't have these genetic mutations, the caucasian must be more evolved and this was demonstrated by European empires that conquered the world at points, none the less, European caucasian countries are among the best in the world, clearly as the African migrated and evolved, clearly natural selection preferred the smarter among the travellers, the dumber ones would die out and so we are left with the caucasian who inherited the best, in a word, it was natural eugenics