I've often wondered too about things like people's skin colour, wisdom teeth, polar bears and these kind of things too.
If people have been living out of the ''tropic zones'' for thousands of years, then their skin colour, complexion is white, blue or hazel eyes. For the most part. People living in the tropics are dark skinned, very dark hair. Studies show that the human body tends to climatize itself in a certain environment. Like people living in Northern Latitudes and those living in equatorial regions. Over thousands of years, humans adapt to their environment, acquiring complexion according to their invironment. People evolve. Same applies to animals. Black bears, grizzlies and polar bears.
Wisdom teeth. Most adults have them. Usually they are too big for someone's jaw. Why is that? Perhaps the human race was larger, bigger boned before??? People evolve.