Re: Why did we get different races under Christianity.
 

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How do you explain the dark skinned inuit? Last I checked, Alaska wasn't exactly all that close to the equator.


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snow will sunburn the [censored] out of you

Re: Why did we get different races under Christianity.
 

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You people learn debate from Dawkins?



LOL irony.


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I'll take that as a yes.

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Did you learn typing from Satan?

Re: Why did we get different races under Christianity.
 

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That seems to be a really poor explanation for the Inuit. Given that they spend most of their time in an environment of snow and ice, even in summer, where the sun reflecting off the pure white can be blinding, it seems like they would develop dark skin for the same reason people near the equator do, protection against the sun. For the dark winter months, it makes no difference what color your skin is, it's dark! Hence, darker skin wins.

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I think you have to understand what the actual selection pressures are, and why black people turned white in some areas. This is my understanding. Near the equator, people get enough sunlight to create enough vitamin D, even though the copious melanin in their skin blocks a significant portion of the UV radiation. They are at a balance, since this same UV also causes cellular damage. As you move to latitudes that receive less sunlight, and less direct sunlight, you get less UV, and thus less vitamin D production, eventually leading to rickets and other problems. So, it now confers a selective advantage to produce less melanin, and there isn't the countermanding negative pressure of cellular damage. So, people tend to get whiter as they move away. However, if you are getting a whole bunch of vitamin D (actually its ACTIVATED vitamin D) in your diet, there is no pressure to develop lighter skin. Since there is no disadvantage to having a bunch of melanin (besides a slight metabolic cost) and since you still have the (albeit lessened) risk of cellular damage from the UV radiation, it makes some sense that you would remain darker skinned.

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This assumes the Inuit came from somewhere where they were dark skinned, zoomed up to the Arctic before their skin could lighten, and then quickly adopted a high Vitamin D diet so there was no pressure to lower melanin in their skin. Seems unlikely.

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Well, the almost certainly came from somewhere where they had dark skin...everyone did. And yeah, the 'zooming' up there thing isn't that much of a stretch, at least on the timescales we are talking about. The diet goes right along with the 'zooming.'