italians testosterone

http://www.worldatlas.com/aatlas/infopage/mediterranean.gif ( open this in a new window)

Mediterranean's have great beards /body hair, off al humans living on planet earth they have the strongest hair development. Its also a fact they have a 40% more testosterone productions then northern Europeans. But why do they have stronger beard development then other ethnic groups? We have to ask ourselves what Is the function of this hair all over our body?

-Well the primary and most important reason is to isolate against 'extreme' temperatures, compare it to a window with double glass, in the winter its warmer then single glass and in the summer its cooler. The layer of air in between helps us isolate.

- The secondary function of body/facial hair is to protect our skin against the sun. U probably already noticed that people living in very sunny countries close to the equator have dark pigmented hair. But then u wonder why do they have black hairs? I remember my physics teachers saying that black attracts heat and a white colour repels it. Wouldn't it be more logic that people living closer to the equator all have white hair to reflect the sunbeams? Well no, because its more interesting than that, the pigmentation in our skin/hair mainly comes from 'melanin' and melanin has this interesting properties against UV radiation.

"They can protect microorganism, such as bacteria and fungi, against stresses that involve cell damage by solar UV radiation or generation of reactive oxygen species"

So the more melanin u have, the better u are protected against those nasty UV beams.

Redheads for example have a very low amount of the dark pigment eumelanin in them, this way there more sensitive to the sun. An estimated 2% of the world's population are redheads and mainly come from countries with are 'northern' and don't have a lot of sun.

To come back to the Mediterranean's and why they have the strongest beard/body hair growth its relatively easy.

All the countries shown on the map have the best environment to stimulate the hair growth, they all border the Mediterranean sea which cools down a lot in the winter and thus giving cold winters and warming up in the summer. Europe also has a good "Circulacion termohalina"( don't know how to translate it) which warms Europe.

So they need a lot of fur to handle this temperature conditions

http://nl.wikipedia.org/wiki/Afbeelding:Circulacion_termohalina.jpg

On top of that these countries are closer to the equator wich stimulates the hair even more to protect against those sun ray's.

Also pls note that facial/body hair are Decreasing, this has several reasons but if u look at it through a very broad scale of evolution the reason is

people wearing cloths and thus the isolation function is not anymore needed of the hair.

And

Oestrogenic remains in water/meat.

I would really appreciate any remarks/opinions/discussion about this threat, also understand that there are still functions yet to discover but this is the best accepted theory so far.

Greets,

Mat


 http://jefffsbeardboard.yuku.com/reply/28328/Re-Why-Mediterranean-s-are-so-hairy#.UNYWsKzmzZw