Why do we have different skin colors?

It is because of a pigment called melanin and ultraviolet radiation of the sun.

Confused?

Obviously.

Alright.

I'll explain.

Millions of years ago, people living near equator received a lot of sunlight and ultraviolet radiation.

Now, ultraviolet radiation is actually absorbed by our skin to produce Vitamin D.

But excess radiation can damage our skin cells.

Hence, the skin of these people produced more melanin to block the excess ultraviolet radiation.

Thus, over time.

These people and their succeeding generations adapted to have a higher level of melanin in their skin.

Making their skin darker.

However, people living away from equator received less sunlight and less ultraviolet radiation.

Hence, in order to absorb sufficient ultraviolet radiation and produce the essential Vitamin D.

These people and their following generations adapted to have a lower level of melanin.

Thus making their skin lighter.