I am pretty ignorant in regards to evolution and traits of different people from different parts of the world....but I would think that we are all from the same stock, but our diets and surroundings are what make us different from a physical standpoint. For example, Asian men tend to be a smaller than American men due to their diets, correct? Africans are dark due to the African sun and Irish are pale due to the overcast weather in Ireland. Common sense!?