On Sat, 12 Jul 2008 22:33:47 -0700, Billy <wildbilly@[EMAIL PROTECTED]
>
wrote:
>In article <u-qdnbTA1Jt9o-XVnZ2dnUVZ_qXinZ2d@[EMAIL PROTECTED]
>,
> "Guv Bob" <brotherdave@[EMAIL PROTECTED]
> wrote:
>
>> Hi Billy. You're an idiot. Bye now.
>
>Now that is a truly a persuasive argument, Boob. Are you sure you
>wouldn't care to exhibit more of your lack of grasp and vacuous
>ignorance?
You have the patience of Job Billy. Too often arguing with a fool is
a waste of breath. O'Reilly and Hannity and Coulter and Malkin and
Marty Seifert... to name a few....are in there
>
>August 27, 2000
>
>UV light, skin color linked
>
>Variations due to geography
>
>Associated Press
>
>SAN FRANCISCO - Two San Francisco scientists using data from a NASA
>satellite say they have discovered why people come in different colors.
>
>Variations in human skin color are the result of adaptations to the
>amount of ultraviolet light from the sun falling on different regions of
>Earth, according to Nina Jablonski and George Chaplin, scientists with
>the California Academy of Science.
>
>People's bodies change their skin color over time to let in just the
>right amount of UV light, which is key to having healthy babies.
>
>UV light affects the skin's production of folate, part of the B vitamin
>complex, and vitamin D-3, both of which are essential for having healthy
>children.
>
>Folate is necessary for the proper development of the nervous system in
>fetuses and for sperm production in adult males. Vitamin D-3 helps build
>and maintain strong bones and a healthy immune system.
>
>But too much solar UV light can not only cause skin cancer, it can also
>damage those chemicals, thereby hurting a person's chances for
>reproductive success.
>
>The scientists' finding may also explain why women tend to be
>lighter-skinned than men. Lighter skin lets in more solar UV light,
>increasing a woman's vitamin D-3 production, which helps the fetus grow
>during pregnancy and helps nourish newborns through breast feeding.
>
>UV light from the sun varies from region to region for reasons including
>latitude, humidity and cloudiness.
>Jablonski and Chaplin's discovery isn't entirely new. For a long time,
>scientists have thought there was a correlation between UV light and
>skin color, and they knew the light helped produce vitamin D and that it
>could cause cancer.
>
>"But this explanation was considered weak by some scientists because
>skin cancer has little or no effect on people's ability to reproduce,
>which is really the bottom line of every evolutionary spreadsheet,"
>Jablonski said.
>
>Jablonski developed the hypothesis that links UV light to reproduction
>in 1991. The scientists analyzed published measurements of human skin
>color from around the world and data from NASA's Total Ozone Mapping
>Spectrometer satellite, which orbited Earth from 1978 to 1993 and
>gathered direct UV measurements for the entire globe to find the
>correlation between skin color and UV light.
>
>Jablonski and Chaplin found that dark skin acts as a natural sunscreen
>to help prevent UV light from breaking down folate, so it is helpful in
>areas with a lot of sun. But in less sunny areas, dark skin screens out
>too much sunlight, and can inhibit the production of vitamin D-3, so
>lighter skin is helpful for reproductive success.
>
>Skin color is based on the level of melanin, an organic molecule with an
>undetermined chemical structure. Those with more melanin have darker
>skin, and melanin levels are genetic. But the variations in skin color
>are adaptations to solar UV light, not biological differences among
>people, according to Jablonski and Chaplin.
>"We're all the same under the skin," Jablonski said.
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