Geografia

Mapa da cor da pele

"To begin, please point your elbow to the ceiling. Then imagine yourself naked. Then look at the patch of skin on the inside of your upper arm, the part of you that almost never sees the sun. Whatever color you see there is what experts call your basic skin color, according to professor Nina Jablonski, head of the Penn State Department of Anthropology. And that color, the one you have now, says Jablonski, is very probably not the color your ancient ancestors had — even if you think your family has been the same color for a long, long time." Robert Krulwich, em Your Family May Once Have Been A Different Color

O mapa em cima mostra as diversas cores de pele no Mundo, mais concretamente a cor média que a população indígena vê se fizer o "teste do braço" descrito acima. A cor de pele torna-se mais clara à medida que nos deslocamos para os pólos, e mais escura, quando nos deslocamos para o Equador. Obviamente, o processo leva muitas gerações, mas aparentemente não serão necessárias assim tantas gerações como se julga:

"Skin has changed color in human lineages much faster than scientists had previously supposed, even without intermarriage, Jablonski says. Recent developments in comparative genomics allow scientists to sample the DNA in modern humans.

By creating genetic "clocks," scientists can make fairly careful guesses about when particular groups became the color they are today. And with the help of paleontologists and anthropologists, scientists can go further: They can wind the clock back and see what colors these populations were going back tens of thousands of years, says Jablonski.

She says that for many families on the planet, if we look back only 100 or 200 generations (that's as few as 2,500 years), "almost all of us were in a different place and we had a different color."

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Geografia