Ah yes, Richard Dawkins, really quite a swell guy. I remember him for his numerous acerbic criticsms of religion.
In a quasi-religious style.
We could all stand to learn a thing or two from him.
Such as why a zoologist should avoid trotting out dogmatic diatribes which make him little different from Bible-bashers? He's very good orator, and can bang on about neo-Darwinism but sees no irony in his near religious devotion to it, nor even its limitations.
ljpdonnelly wrote:You realise when the world was one big continent ,pangaea or something like that, we were all black.
Protection against UV radiation is *one* effect of melanin; possibly even an advantageous side-effect. Native populations in fiendishly hot areas, such as Central America, aren't too black. Melanin is produced by skin cells not exposed to sunlight, such as in the nostrils or rectum. Various theories have been positted for this, such as how "sticky" a molecule it is thus soaking up pathogens and toxins which abound in tropical regions. The blackest of the black humans are Australian Aborigines, which also represent some of the oldest populations of modern humans.
but as we moved to places with less exposure to sun we lost our dark skin
Again, that is simplistic. A healthy diet can often provide more than enough Vitamin D. Cases of rickets became notorious in dank industrial towns where white-skinned people were not exposed to the sun, or subsisted on a crap diet. They have also been reported in deep Alpine valleys. Also, there's a lot to suggest that melanin makes bones highly dense (this is often apparent when X-raying Africans!).
It's been suggested that the presense of melanin also makes one susceptable to the effects of cold, which migrating humans would have experienced in the hyperboreal north. Consider the image of "frost-bitten" Senegalese in WWI.
Why was LJ banned?
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