No, no, see, what'll happen is the people in the third world countries will devolve into the inferior human subspecies, and they'll be dark skinned, because most third world countries are filled with dark skinned people. And the people in modern western countries will evolve into the superior human subspecies, and they'll be white, because the people in modern western societies are primarily white. And then the ugly darkies will constantly resent their aryan masters, but they won't be able to rebel or anything because they're inferior on a genetic level.
Yay science!