A question about black and white skin

[Diceroller]

Why is it that people in hot countries get dark skin whilst those in cold countries do not, before I'm made out to be crazy let me explain. In hot weather I usually wear light coloured r white clothes as they reflect light and heat and keep away from dark or black clothing as it attracts heat so why is this the opposite with skin colouring? It seems that dark skin is better for the sun and white skin burns and isn't too good why is this the total opposite with clothes? What's the explanation for this I appologise if my question is all over the place but I have been ill recently.

[Diceroller]

(And yes I know that most skin is not actually black or white but you get the gist of what I'm asking I hope)

[bookbinder]

Skin is skin, and clothes are made of fabric. Two different substances that react in different ways.

[sandyRoe]

Melanin protects people from the harmful effects of radiation from the sun. People living near the equator would need more than those living further north.

[Chaffinch]

The skin produces melonine which gives it its colour. In hotter countries it produces more melonine (pigment) making it darker, thus helping to protect it somewhat. Though dark skined people can still get sun burnt.

[Calibax]

The black pigment in skin is a form of melanin which protects against UV light. It absorbs harmful UV-radiation and transforms the energy into harmless heat. It is not a protection against heat.
Also, as well as being good at absorbing heat, black is also good at radiating heat so if you sit in the shade dressed in black you may actually be cooler than if you wore white.

[Sqad]

I agree with all the posters re. melanin.

But new born babies of parents with black skin.........are born with black skin before being exposed to the sun.

;-)

[sandyRoe]

That's just Mother Nature's way of ensuring they don't get sunburnt in their prams

[Sqad]

SANDY...\LOL....but how does "Mother nature" know that there are going to be born in the tropics.....they may be born in Streatham.

[sandyRoe]

There's sunshine in Streatham, sometimes

[Sqad]

sandy....LOL....so they tell me.

[joko]

because one is about simply the reaction to light and heat on a colour and its reflective qualities, and the other is about heat and uv rays on different types of skin...

[Old_Geezer]

Clothing colour is interesting since, for example, different Arab tribes favour different colours. There was a programme on TV about it once, with dark colours being good for one cooling advantage, and light ones for another. I think you pays your money and takes your choice.

As for skin colour, I am convinced it is merely generations of personal preference of the local people. Evolution and all that favours sexual selection preferences. How else would one account for yellow and red skinned people ? Ok there may have been such a preference because the local folk believed there was an advantage to taking darker skinned partners, but that's for the psychologists to comment on.

[BillyBB]

Vitamin D.
Paler skins produce more Vitamin D from less sunlight than darker skins. So further from the equator you need paler skin to avoid rickets.
It appears that the great continent of Africa was the cradle of mankind so those ancestors that ventured further north or south have slowly evolved paler skin as we can maintain our health better under dull grey skies.
Similarly those with paler skin living closer to the equator would have suffered rather than thrived.

[ossian]

Surely the key question is "Why do those people who live at high latitudes not have black skin?". Although there is much less sunlight and much weaker sunlight at higher latitudes and the need for melanin much reduced it should still be of some significance and, of course, there would be the additional advantage in that black skin will be more efficient in absorbing the suns's rays in winter. What advantage does white skin confer at high latitudes? Stew.

[ossian]

I understand that white skin may be better at producing Vitamin D and while it is true to say that those who live at the highest latitudes have in general a paler complexion than those who inhabit equatorial latitudes it is certaintly not white, as we understand that term, for example the Innuits and many of the Asiatic tribes of northern Siberia. It is a very complex matter with many variables. I think that Old_Geezer may have a point. Stew.

[boxtops]

I understand that people with black skin can still get sunburned.