BECAUSE YOUR CONCEPT OF RACE IS WRONG, they are produced by geographic , social and historical ISOLATION. The fact I can marry with 3 women from different races and they beget characteristics of each one of them and me indicates all possible features are within our DNA, hence if you get back enough in time the first ADAMU, ADAM or homo sapiens did have MINGLE featuresof all races and not just "white", yellow, black, brown or redhair....