Compléter Skin ColorVersion en ligne The color of human skin and its relation to the synthesis of vitamin D par Jorge Arizpe 1 melanin darker Theory vitamin suffering successful reproductive randomly Since ancient times , it has been clear that the color of human skin is not distributed on the planet . The skin of the inhabitants of the Ecuadorian region is , while the skin of those who inhabit colder regions is clear . A recent hypothesis proposes that the variety of colors is an adaptation that allows the inhabitants of different environments to maintain the levels of D and folate that their organisms need . " It's not that race does not exist , " wrote anthropologist Jonathan Marks , " . . . it's that race does not exist as a biological entity . Race undoubtedly exists as a symbolic and social category . Scientists prefer to talk now about human populations that have their own and visible characteristics ( skin color , hair type , eyelid shapes , face and body ) . Human skin , whose color varies between the dark brown of Central Africans and the pale pink of Northern Europeans , owes its color to the presence of a pigment called melanin . The amount of - producing cells is more or less the same in all people . What varies - and originates the diversity of colors - is the amount of pigment produced . Melanin in the skin plays an important protective role by absorbing ultraviolet ( UV ) radiation . The Sun emits different types of UV radiation . UVA radiation reaches the blood vessels that supply the deepest layers of the skin and destroys the folate transported by the blood ( an essential nutrient for DNA biosynthesis ) . It is true that dark skin is less prone than clear skin to develop cancer by exposure to UV radiation . However , this type of cancer is not usually fatal during the age . According to the of Evolution , a characteristic is considered when it favors the reproductive capacity of those who possess it . Science has shown that the concept of human races lacks biological foundation , and that the coloration of the skin can be explained in terms of adaptations to different environments . Will these findings be sufficient for race to cease to exist in the minds of fanatics and profiteers , and for the color of their skin to cease to be the source of for millions of people ?
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