Everyone knows that Africans have dark skin. Not everyone knows this, but if you look closely, you will definitely notice this fact.
Why didn’t nature endow them with uniform, uniform skin color? And why exactly these parts of the body remained bright, albeit not pure white, as in Europeans, for example? It turns out that science can answer similar questions.
Melanin and its distribution in the skin
To understand such issues, you need to understand where the dark skin color comes from. So, it is provided with the pigment melanin. The pigment is produced by the organisms of all people, with the exception of only albinos. When you relax on the beach and get a tan, it is the release of melanin.
This pigment is extremely important for protecting the body from ultraviolet radiation. Among Europeans, it stands out as a protective reaction in cases where the body is exposed to intense sun exposure. You can understand how important such protection is if you look at the problems of albino people who simply cannot be tanned.
Since their skin does not have protection, sunburn with all the ensuing consequences can form in them very quickly. Among black people there are also albinos, but this is rare. In general, representatives of African nationalities have melanin in the skin constantly - from the first days after birth.
Interesting fact: The children of black parents are born light.Their skin integrates dark color in the first hours or days after birth.
Why is the excess of melanin not represented in all of humanity?
Given the importance of UV protection, a logical question arises. Why isn’t all of humanity endowed with dark skin? And why do residents of temperate latitudes lose their tan after the summer season? It turns out that the production of melanin is an “expensive” pleasure for the body, it requires a lot of valuable substances and resources that could be directed into a channel that is more useful for northerners. In conditions of moderate solar activity, such savings are quite advisable, while in Africa this is unacceptable. Because the skin of Africans does not change its color.
But nature has found another loophole that allows at least a little to save the efforts of the body. So, least of all body parts suffering from the sun have virtually no melanin - and therefore remain light. Of course, we are talking about the feet and hands.
However, why does the skin remain dark in the armpits, for example? After all, the sun does not get there too often? Here it is immediately worth noting that the skin in the armpits and other areas that could be completely deprived of protection is thin and delicate, in addition, there are lymph nodes and other critical areas under it. It turns out that nature was right again, without creating unnecessary risk.
As for the skin of the palms and soles - it not only does not cover critical areas, but also differs in rigidity, multi-layer, rather rough, is constantly exposed to physical impact, and therefore it is quite advisable to save on melanin within these areas. After all, its very density and callosity will already be quite sufficient protection.
In addition, some experts proceed from the opposite and indicate that it is the roughness of the skin on the soles of the feet and palms of the hands that prevents the production of melanin. And this is noted not only among Africans, but also among all peoples existing on our planet. If you try to sunbathe with your palms or soles exposed to the sun, tanning will not appear on them. But to burn the skin in these areas under the scorching sun is quite realistic, if you overdo it.
Thus, Africans are distinguished by light soles and palms, because melanin is not produced in these areas. And this is true for all of mankind - due to the corpus callosity of the skin in such areas, as well as due to the lack of the need for their protection from ultraviolet radiation, they always remain bright.
