Actually there are several genetic differences between black and white. Most of them are evolved from environment. Like whites have white skin because of winters and vitamin D intake. Black people on the other hand have tightly curled hair for coping with hot dry weather as in it keeps their heads cooler when they are out in the sun and dark skin to help protect from burning. Their nostrils are wider because many are decended from hunters and needed to have more air for long hunts and it also helps keep the body cooler by that intake. As for the lips, I have no clue so no speculation there. They are more aggressive because of mating and survival against other aggressive tribes where you have to kill to be able to not be killed and the mating is women get hot for alpha type males and you can tell that by checking out who leaves first with the hot girls in a bar.