As modern humans spread out of Africa in the past 60,000 years, they adapted to the varying natural light they encountered, from the twilight of northern winters to the blazing sun of the equator, and their originally dark skin evolved into a sepia rainbow.


The researchers found a mishmash of evolution in various places across Europe and three different genes that are producing the light skin. It is presumed that the modern human, who came out of Africa to settle in Europe roughly 40.000 years ago, had a dark skin tone.

An explanation for there change in complexion  is that a dark skin is advantageous in sunny areas, but the lower light levels in Europe made this no longer useful. This was no longer useful, because in the northern areas of Europe people often didn’t get enough UV to synthesize vitamin D. Natural selection therefore favored a genetic solution to that problem by evolving to a pale skin that absorbs UV more efficiently.

Skin color has crucial implications to health for example, most white people know that if they live near the equator, they risk skin cancer unless they use sunscreen. But what is less known is that dark-skinned people who bundle up in frigid northern winters or stay indoors all day in the tropics risk vitamin D deficiency, making them susceptible to rickets, infectious diseases, heart disease, and other health problems.

But further tests are still going on to find out how sunlight affects human health.