If modern humans came from africa, what explains the loss of pigmentation seen in different races?

Its hard to explain but i will do my best now not to insult anyone but a long long time ago people would produce heirs with their own kind because they had no way of transportation to get to a different area their fore meet people of a different racebig idea is races are losing their genes because we have a wider variety of people so the newest generation of children are not just Spanish or asian or dutch or any simple race their a huge mix of races and no one is a specific color (if you will) will be darker or paler. hope this helps you understand a bit more 

The process that fuels our sun and allows it to give off that much energy is called nuclear fusion.