2007-07-29 15:57:17 · 13 answers · asked by Anonymous in Society & Culture ➔ Religion & Spirituality
Okay look, I'll be a nice guy answer this one. But after this, please for the love of science research this stuff yourself so you don't come off as an idiot. The gene that made melanin appear white was just a genetic mutation that spread. Scientists have pinpointed it so we know it exists and that's why.
2007-07-29 16:00:16 · answer #1 · answered by Anonymous · 2⤊ 0⤋
humans synthesise vitamin D in their skin, with exposure to UV light. in non-tropical regions dark-skinned humans can't absorb enough UV to make sufficient vitamin D (since the melanin pigment in dark skin blocks UV), and this has adverse health effects. natural selection therefore favors humans who have genes that result in less melanin being expressed, and that means lighter skin. the first migrants from africa would have had to have acquired a novel mutation, but subsequent migrants more likely acquired the gene(s) by interbreeding with locals.
2007-07-29 23:07:53 · answer #2 · answered by vorenhutz 7 · 2⤊ 0⤋
Because the further you get from the equator, the more important your ability to synthesize vitamin D from sunlight becomes. Light skinned people as a group survived better the further they got from the equator, and vice versa.
2007-07-29 23:02:32 · answer #3 · answered by Anonymous · 1⤊ 0⤋
people's skin tone changes along with climate. if people moved more north..their skin became lighter. if that stayed towards the equator...the darker they got....i also don't believe that we all came from Africa. i think that civilization started in the middle east.
2007-07-29 23:00:29 · answer #4 · answered by Ms. Lady 7 · 1⤊ 0⤋
Evolution
atheist
2007-07-29 23:04:35 · answer #5 · answered by AuroraDawn 7 · 2⤊ 0⤋
I don't know off the top of my head but it is either natural selection or genetic drift. Try wikipedia.
2007-07-29 23:00:48 · answer #6 · answered by Anonymous · 3⤊ 0⤋
we evolved to suit our climate. i would assume that darker skin does better in the sun than lighter skin.
2007-07-29 23:00:58 · answer #7 · answered by Anonymous · 3⤊ 0⤋
Adaptation over time to climate, any other questions genius?
2007-07-29 23:04:12 · answer #8 · answered by Anonymous · 1⤊ 0⤋
Because we all didn't come from africa
2007-07-29 23:00:10 · answer #9 · answered by Love not hate 5 · 0⤊ 4⤋
because of evolution, Einstein.
2007-07-29 23:01:17 · answer #10 · answered by Anonymous · 4⤊ 0⤋