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Old 06-28-2014, 02:20 PM
 
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In terms of science - darker skin would keep you warmer when the sun hits you. Yet people in warmer climes have darker skin. Why would evolution cause this to happen?

I also wonder why the original people were in Central Africa and had very dark skin but as they moved northward and eastward they started to have lighter skin. Also why do Asian people have a different shape of eyes?
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Old 06-28-2014, 02:46 PM
 
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https://www.google.com/search?q=Why+...sm=93&ie=UTF-8
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Old 06-28-2014, 02:48 PM
 
Location: SC
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Evolution at it's most obvious incarnation.
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Old 06-28-2014, 08:25 PM
 
Location: God's Gift to Mankind for flying anything
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Quote:
Originally Posted by robertpasa View Post
I also wonder why the original people were in Central Africa and had very dark skin but as they moved northward and eastward they started to have lighter skin. Also why do Asian people have a different shape of eyes?
Dunno about skin colour, but why the eyes of Asians are more almond shape ...
That is because of the diet --- too much rice !
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Old 06-29-2014, 06:31 AM
 
Location: near Turin (Italy)
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The skin color depends on the concentration of melanin. Melanin is a molecule that protect the skin from an excess of UV rays, that are the most energetic radiations produced by the Sun that reach the Earth surface. Nearer you are to the Equator more perpendicular are the light rays and bigger is the concentration of UV rays. High concentration of those radiations could be dangerous, so the evolution brought to an high concentration of melanin in the people who live in places with a more direct solar exposition. that's why people who live nearer the equator have the darkest skin.
But low concentration of UV rays are necessary for the synthesis of D-vitamin (that it's indispensable for the bones' health). Near the equator could pass enough UV rays also trough the darkest skin, but at higher latitude (where the UV radiation is weaker) the amount of melanin has to decrease to allow the production of D-vitamin. So when the first human population reached Europe and Asia the evolution brought to a lighter skin.
So in practice the amount of melanin must allow to pass enough UV ray to synthesize right quantity of D-vitamin, but not so much to damage the skin.
The amount of melanin it's also quite variable, when you expose to a stronger radiation than usual your skin produce more melanin and you get tanned.
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Old 06-30-2014, 05:16 AM
 
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Probably has to do with aliens who visited Earth in the distant past,some stayed,lived long and prospered.
https://www.google.ca/#q=did+humans+...ns&safe=active
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Old 06-30-2014, 04:10 PM
 
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So being born dark skinned have it's advantages over an Albino person?.........Okay, lets pour on the UV. Seriously it is DNA, and the DNA tells a person if they are going to have dark or light skin irregardless of their race. It is an 1n1 shot of either. The skin color can be dominant or recessive, depending on combination. Most studies are cherry picked on this topic. However like somebody said, the Melon in the skin is what affects coloring. Melon itself is also BROWN, and an certain percentage is, everybody skin.


About Aliens. Maybe people who are darker, come from space, and traveled from a distant galexy, or star. Thus they have more Melon to protect them from the UV rays. Then again people who are lighter are really Mole people, who lived eons, inside an metal city. No seriously it is your genes.
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Old 06-30-2014, 04:48 PM
 
Location: Someplace Wonderful
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Originally Posted by jambo101 View Post
Probably has to do with aliens who visited Earth in the distant past,some stayed,lived long and prospered.
https://www.google.ca/#q=did+humans+...ns&safe=active
Isnt there a Coast to Coast forum where posts like this should be?

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Old 07-01-2014, 01:06 AM
 
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Originally Posted by chuckmann View Post
Isnt there a Coast to Coast forum where posts like this should be?

Whats your opinion for the Earths racial diversity?
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Old 07-01-2014, 01:52 AM
 
Location: Out there somewhere...
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Originally Posted by jambo101 View Post
Whats your opinion for the Earths racial diversity?
George on Seinfeld said it best "when world's collide".


Independent George - Worlds collide - YouTube
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