On a related note (I was going to put this in "What have you learned today?" thread, but works here), apparently early humans (and related species) got Vitamin D from eating lots of meat. It was only when some groups moved to a more plant based diet that they needed more Vitamin D from the sun, and so in places away from the equator they became paler.
Neanderthals, with their high meat diet, would have remained dark skinned, and natives of Tasmania, which were isolated for many thousands of years, retained a high meat diet and so never became paler, despite being at a latitude that has produced paler people elsewhere with different diets.