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Naked skin or effectively naded skin has been the primary interface1 between the human body and the environment for over 200,000 years.
Penn State anthropologist2 Nina Jablonski on the evolution of human skin pigmentation at the annual meeting of the American Association for the Advancement3 of Science in Boston on February 16th.
The variation in pigmentation is one of the most conspicuous4 and interesting features of human skin. In fact that within one species we have a wide variation skin pigmentation from very dark to very light, and that this pattern has a sensible geographical5 distribution that is related to the intensity6 of UV radiation is highly significant.
Ultraviolate radiation exerts such negative effects, predominantly negative effects on the body, strong malinen pigmentation evolved to protect us from most of those negative effects.
Loss of pigmentation was one of the most conspicuous things that occurred in these few small populations of homosapiens that left Africa arround 17,000 years ago. So that we actually see depigmented skin evolving in the ancestors of Western Europeans and Eastern Asians independently as a a result of independent genetic7 mutations, because this depigmented skin was very important to people living under low UV regimes. It allowed people to make Vitamin-D more easily out of available UV radiation in sunlight and it afforded tremendous evolutionary8 advantages.
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1 interface | |
n.接合部位,分界面;v.(使)互相联系 | |
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2 anthropologist | |
n.人类学家,人类学者 | |
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3 advancement | |
n.前进,促进,提升 | |
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4 conspicuous | |
adj.明眼的,惹人注目的;炫耀的,摆阔气的 | |
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5 geographical | |
adj.地理的;地区(性)的 | |
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6 intensity | |
n.强烈,剧烈;强度;烈度 | |
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7 genetic | |
adj.遗传的,遗传学的 | |
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8 evolutionary | |
adj.进化的;演化的,演变的;[生]进化论的 | |
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