Human beings are very adaptable to exposure to sunlight. Melanin production can shift in a population in as little a three thousand years, a heartbeat in evolutionary terms. Many people think that the white skin of Europeans is an adaptation to the cold. It is not. The body shape of Inuit people and the eye folds of east Asians are adaptations to the cold. The European’s white skin is an adaptation to lack of sunlight. Now, of course, the further north one goes the less sunlight you receive but the native peoples of the far north, the Inuit, while much lighter than peoples living near the equator, are much darker than Europeans. Here’s why:
All white people originated in a small area of central Asia around the Baltic and Black seas. This area is unique in the world. Due to prevailing wind and ocean currents it is very dimly lit relative to other places in the same latitudes. However, the warm currents also make it warm despite the low light. Why is this important? Because cereals grow in this region as the result of the relatively warm temperature. Most people living in this kind sub arctic light must eat meat because grain will not grow. The people of the Baltic region were cereal eaters. You don’t get vitamin D from cereal the way you do from meat and animal products so it must come frm sun exposure. So, to increase the production of vitamin D from the dim light these people quickly lost their melanin, not just in their skin but eyes and hair as well in a process known as “neotony”.
Human beings of all races are often born with light skin and hair and blue eyes which darken shortly after birth. Sometime about 14,000 years ago this population was introduced to a genetic mutation which preserved this infantile state into adulthood. Another more controversial theory is that this adaption to low sunlight was inherited from the Neanderthal through interbreeding. The decoding of the genome of neanderthal indicates that they also had low levels of melanin and red hair and ruddy skin. Perhaps, this isolated pocket between these two seas and the Caucasus Mountains was the last refuge of Neanderthal. In any case these pale people remained in their dark homeland eking out a marginal existence for about nine thousand years barely surviving. Then suddenly they burst out from this place in all directions conquering their way across the continents of Asia and Europe in what was known as the Aryan invasions. A remnant of these people still remains in this area known as the “Circassions”. Converted to Islam in the 18th century, they are renowned for the beauty of their women and the warrior spirit of their men. Source
Melanin is a pigment that is being found in most organisms. In humans, melanin is the primary determinant of skin color. It is also found in hair, in the iris of the eye, at the inner ear and some parts of the brain.
The melanin in the skin is produced by melanocytes, which are found in the basal layer of the Epidermis.
Although, in general, human beings possess a similar concentration of
melanocytes in their skin, the melanocytes in some individuals and
ethnic groups more frequently or less frequently express the melanin-producing genes, thereby conferring a greater or lesser concentration of skin melanin.
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