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Has 'nature' Made A Mistake

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optomist | 17:00 Sat 16th Mar 2013 | Science
10 Answers
It is known that black absorbs heat and white reflects it so why do indiginous
peoples of equatorial countries have very dark skins. conversely, other populations have lighter and lighter skins the further they are from the equator.
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Heres a theory http://www.thenakedscientists.com/HTML/questions/question/2560/
17:02 Sat 16th Mar 2013
Does black actually absorb heat? I'm sure I read somewhere that it was a myth.
No. Nature has got it the right way round.

Skin cancer is extremely rare among dark-skinned people, simply because nature has provided their skin with the ability to produce extra melanin to protect them from harmful UV radiation.
Populations away from the equator need lighter skin for greater absorption of the limited sunlight / vitamin D synthesization.
Although balck absorbs heat, it dissipates it faster then white. Hence you nearly always see desert dwellers wearing black. There you go !!
FBG40
If a dark skinned person isn't daft enough to stand in the midday sun the dark skin radiates more heat from the body.than it absorbs.
Nature never makes mistakes but sometimes isn't very good at seeing into the future.
it is obvious that heat absorption isnt the deciding factor

(although they tend to get taller and leaner towards the equator and this minimizes heat absorption (cross area thingey) and so heat absorption DOES matter in habitus)

it is to do with melanin and protection from photo-damage.
No.

The black colour is derived from melanin in the skin, which acts as protection against UV radiation, which causes all sorts of damage to some pretty important systems within the body.
Also, Nature's "mistakes" don't last long enough to breed.

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