Word: keratin
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Dates: during 1960-1969
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Reverse Selection. There remains the question of why the Mongols and related peoples are "yellow." Biochemist Loomis explains this on the basis of additional keratin (horny material) in the outer skin layers-though dermatologists deny this and say that the Mongol's sun screen is melanin, like the Negro's, but in smaller amounts. Loomis surmises that the yellow races may have developed their coloration after having gone through the white-race depigmentation phase. If migration away from the equator produces lighter skins, says Loomis, reverse migration could have the opposite effect. In the mere...
...least part of it and carries some in his hand throughout life. Babies of all races are lighter than adults, presumably reflecting nature's provision for early vitamin D needs. And people of all races have pale, unpigmented palms and soles. Since these parts have extra keratin and are not exposed to ultraviolet, they need no melanin protection against excess vitamin D synthesis...