Why do Africans 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 bodies. 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, leading to sunburns, premature aging, and increasing the risk of skin cancer. In populations that have historically lived in regions with intense insolation, such as Africa, a genetic trait that results in high melanin production has been fixed 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 understanding this lies in the fact 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 downward 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 perspective, it would be energetically disadvantageous for the body to produce an expensive pigment in areas where it is not urgently needed. Nature optimizes resources, and therefore, intense melanin production on these areas was not fixed 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. Biological mechanism: tyrosine and the tyrosinase enzyme Th ... Read more