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Melanin, the pigment that determines the color of skin, hair
and eyes, is produced in cells called melanocytes, as you
know. The amount of melanin is one of the factors that
determine the races.If melanin is not formed by the
melanocytes the skin becomes lighter or completely
white and more melanin a skin has, darker it turns.
The need of melanin is to protect the skin from the UV
radiation that comes from the sun light.
The species adapt themselves according to their needs.
So the Africans skin during the millions of years of
evolution become dark and darker to protect from
the high temperatures and sunburn. But due to the
same adaptation the body parts that are less
exposed to the sun, as the palm hands and the soles
feet got less melanin because it was lesser
needed. As a consequence they are lighter.
So is nature...very wise...
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