If modern humans came out of Africa 300,000 years ago, how did everyone who isn’t black get their skin colours?

Question

If modern humans came out of Africa 300,000 years ago, how did everyone who isn’t black get their skin colours?

In: 4

Answer 1

The simple answer is mutation.

Some populations that left Africa mutated, and because of that mutation had more success in the new biomes they were inhabiting. They spread that mutation through their children until it became dominant in the areas they now inhabited.