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Evolution of black skin in early humans might have happened to protect against a very high risk of dying from ultraviolet light (UV)- induced skin cancer, according to a new study. 

Until now, researchers have ruled out the idea that skin cancer is the most likely selective pressure for the development of black skin. According to them, it is only rarely fatal at ages young enough to affect reproduction. 

However the new study has cited evidences that black people with albinism from parts of Africa with the highest UV radiation exposure almost all die of skin cancer at a very young age. The place is also the same where humans first evolved. 

The research cited the studies showing that more than 80 percent of people with albinism from African equatorial countries such as Tanzania and Nigeria tend to develop lethal skin cancers before the age of 30. 

Although few researchers have agreed on the notion that the development of black skin occurred in early humans mainly because of the ability of eumelanin to absorb ultraviolet radiation, but they have debated exactly how this might protect early humans against the lethal diseases. 

"Charles Darwin thought variation in skin color was of no adaptive value and other investigators have dismissed cancer as a selective force in evolution. But the clinical data on people with albinism, particularly in Africa, provide a strong argument that lethal cancers may well have played a major role in early human evolution as an important factor in the development of skin rich in dark pigmentation - in eumelanin," said Professor Mel Greaves, Director of the Centre for Evolution and Cancer at The Institute of Cancer Research, London in the press release. 

The development of the study is published in the Proceedings of the Royal Society B.