What about white people? If we're descended from apes, how comes some of us are white and some of us are black and some of us are of varying shades of "in-between"...?
- first of all, we are not descended from ape, we are an ape.
- second, your question seems legit and actually interesting. In your world view of Adam&Eve as father and mother of all humanity and natural selection is bullshit, how do YOU explain skin color?
- Now here is how evolution explains skin pigmentation:
The differences in the skin colors of human are due to environmental adaptation.
If you look at the population distribution, you see that there is a strong correlation between the light level of the environment and the color of the skin. So our skin pigmentation (level of melanine) seems to be correlate with the level of UV our skin recieve.
From what i researched, there is no conclusive answer to the why.
A hypothesis to why people living in an area with high level of UV have a dark pigmentation would be that a dark pigmentation protects you against skin cancer (melanoma) and hypervitaminosis D (too much vitamine D). At least that was what people thought, but more recent studies seems to indicate that this is not the cause, the selective pressure isn't strong enough to explain skin pigmentation.
Instead, another study shows that folate (folic acid) one of the B vitamins that plays a crucial role in biosynthesis, including DNA synthesis and repair, is destroyed by sunlight in the blood vessels of the skin. An absence of folate could cause neural tube defects (NTDs) in human embryos, serving as a potent selective pressure.
Now the reason why people living in areas with less solar radiation are lighter is that we need vitamine D for a lot of things (building bones, immune system, brain, etc ). When the light level is strong, we recieve enough vitamine D even if our skin pigmentation is dark and blocks most of the light. So when people migrated to places with less light, they got vitamin D deficiency, and our skin gradually adapted to be lighter in order to ensure an adequate amount of vitamin D.
You will probably find more info in this video (the speaker is the author of the studies i refered to):
The Evolution of Human Skin Pigmentation (60min)
https://www.youtube.com/watch?v=wfZHikOARc8
Edited 4/22/2015 08:43:28