Dark skin is a human skin color that is rich in melanin pigments, especially eumelanin. The evolution of dark skin is believed to have begun around 1. In the heat of the savannas, better cooling mechanisms were required, which were achieved through the loss of body hair and development of more efficient perspiration. The loss of body hair led to the development of dark skin pigmentation, which acted as a mechanism of natural selection against folate depletion, and to a lesser extent, DNA damage. The primary factor contributing to the evolution of dark skin pigmentation was the breakdown of folate in reaction to ultraviolet radiation ; the relationship between folate breakdown induced by ultraviolet radiation and reduced fitness as a failure of normal embryogenesis and spermatogenesis led to the selection of dark skin pigmentation. By the time modern Homo sapiens evolved, all humans were dark-skinned. Humans with dark skin pigmentation have skin naturally rich in melanin especially eumelanin , and have more melanosomes which provide a superior protection against the deleterious effects of ultraviolet radiation. This helps the body to retain its folate reserves and protects against damage to the DNA. Dark-skinned people who live in high latitudes with mild sunlight are at an increased risk — especially in the winter — of vitamin D deficiency. As a consequence of vitamin D deficiency, they are at a higher risk of developing rickets , and numerous types of cancers, and possibly cardiovascular disease and low immune system activity.
The fair maiden of myth appears to have a basis in scientific reality, according to new research. Scientists looking into attractiveness in men and women suggest that men of all races are subconsciously attracted to fairer-skinned women, while women are more drawn to dark-complexioned men. The researchers, whose study shows that across different races, lighter-skinned women are seen as the ideal, say the attraction is driven by preferences based on moral assumptions. Men are subconsciously attracted to fairer skin because of its association with innocence, purity, modesty, virginity, vulnerability and goodness, according to researchers at the University of Toronto. Women are attracted to men with darker complexions because these are associated with sex, virility, mystery, villainy and danger.
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