We say that people can be black or white, but with these two colors the richness of the color shades of human skin is by no means exhausted. The color of a person’s skin mainly depends on where, in what place of the planet his ancestors lived.
Scientists have experimentally confirmed theories about how people have different shades of skin color (but so far they are just theories).
What determines skin color?
Skin color depends on a substance called melanin. The more melanin in our skin, the darker it is. When a white-skinned person spends a lot of time in the sun, then a lot of melanin is formed in his skin, in other words, he tans. Albinos, which lack melanin in the body, have pinkish skin and reddish eyes. This color is due to the transmission of blood vessels through the skin and colorless tissues of the eye. Albinos have completely white hair.
What is melanin for?
The deposition of melanin in the skin is its protective reaction to the ultraviolet radiation of the sun, which can cause skin cancer. As a light shield, melanin absorbs ultraviolet rays and helps protect the skin from damage. The more melanin in the skin, the darker it is and the better protected from ultraviolet radiation. Knowing the great importance of the presence of melanin in the skin, scientists developed the idea of how differences appeared in the amount of melanin deposited in the skin in different human races and how these differences developed over millions of years.
Interesting fact: A large amount of melanin in the skin protects it from ultraviolet radiation.
How did people get different shades in skin color?
Our distant ancestors were covered with a thin layer of wool that protected their skin from intense ultraviolet radiation from the hot African sun. Hundreds of thousands of years have passed. With the development of humanity, people began to be born cubs, deprived of hair on the body. Why? No one knows this. But gradually the light spotted skin of our ancestors turned out to be completely unprotected from the scorching rays of the sun.
Since dark skin protects better from the sun, those individuals who were born darker than their counterparts received an advantage in terms of survival. Since the dark skin color was inherited and had the advantages of natural selection, over time, the skin color of the inhabitants of Africa became dark. People have spread throughout the earth. Those who fell into the cold north found a far from African climate there. In Europe, for example, sunlight is much weaker, especially in winter. This climate also has its drawbacks.
Too many ultraviolet rays are harmful, but too few are even worse. Ultraviolet rays are vital for us: under the influence of this radiation, vitamin D is produced in the skin, without which the formation of strong, strong bones is impossible in the body.
Interesting: the very first humans may have had light spotted skin, similar to chimpanzee skin under its fur.
The dimmer light of the European sun contains far less ultraviolet rays than sunlight in Africa.The first problems arose probably in black aliens whose skin blocked the small amount of ultraviolet radiation that remained in the rays of the northern sun. Some children developed rickets, in which the bones became soft and fragile, they easily bent and broke.
Therefore, in Europe, children born with a lighter skin tone received an advantage in terms of survival. And again, over time, people with white skin have become more numerous than black people. In weak winter light, pale skin remains permeable to ultraviolet rays, the child receives a sufficient amount of them, vitamin D forms in his skin, and he does not get rickets. But in bright light in summer, pale skin tans and transmits ultraviolet rays to a lesser extent.
Skin color and climate
As a person mastered the spaces of our planet, skin color adapted to the climatic conditions in which people found themselves. The lightest skin in people who live under the pale sky of Scandinavia. In a more sunny climate, skin color can range from golden to light brown. The darkest skin in the inhabitants of Africa and Australian Aborigines. Recently, as people began to move more freely around the world and enter into mixed marriages, the clear division into races has been violated, and now people with different skin colors live in any climate.
