Cur why do African people have light hands? Evolution and melanin
The phenomenon of light hands and feet in people with dark skin is a vivid demonstration of the work of evolution and the complex biology of our body. The reason for this difference lies not in different types of skin, but in the activity of specialized cells — melanocytes, which produce the pigment melanin, responsible for the color of the skin, hair, and eyes.
The role of melanin: natural protection from ultraviolet light
The main function of melanin in the skin is to protect the deeper layers from the harmful effects of ultraviolet (UV) radiation from the sun. UV rays can damage the DNA of cells, which can lead to sunburns, premature aging, and increase the risk of skin cancer. In peoples who have historically lived in regions with intense insolation, such as Africa, a genetic trait that causes high melanin production has been consolidated through natural selection. This gave them a vital advantage — effective protection from the sun.
Evolutionary appropriateness: where protection is needed and where it is not
The key to the solution is that the palms of the hands and the soles of the feet have not been exposed to direct sunlight during the course of evolution.
Palms are usually turned down or used for gripping, manipulating objects in the shade.
Feet are constantly in shoes or in contact with the ground, protected from direct rays.
From an evolutionary point of view, it would be energetically disadvantageous for the body to produce an expensive pigment in areas where there is no urgent need for it. Nature optimizes resources, and therefore, intense melanin production in these areas has not been consolidated by natural selection. This principle is universal — the skin on the palms and soles of all people, regardless of race, is lighter than on other parts of the body. Simply, in people with dark skin, this contrast is visually more noticeable.
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