Was reading more about this today and thought there was some interesting info. It was saying that the Vitamin D link to pale skin didn't apply to hunter gatherers because they got enough Vitamin D from their diet. It suggested the pale skin gene came later when farming people came across from europe 6,000 years ago. It said due to the different diet of these people which was low in Vitamin D pale skin, allowing the vitamin to be better synthesized from sun light, gave a survival advantage. The reason pale skins became dominant was due to numbers arriving and the subsequent change in life style.