The connection between vitamin D production and skin color is clear when we look at evolution. The earliest humans lived in Africa, their dark skin produced less vitamin D because of their dark skin. As a result, their skin made less melanin, so they could get enough sunlight to produce vitamin D. their skin gradually got lighter and they lost hair. Now, people living in areas with strong sunlight like Africa, have darker skin, while people living in other areas have lighter skin. The exception to this is the Inuit, who live in a place with little sunlight, but have dark skin because they eat a lot of fish and have enough vitamin D.

　　Evolution has given us a rainbow of skin colors. Humans have always had melanin to determine our skin color. What has changed through history is the environment where we have lived. This has in turn changed our melanin production, and eventually, skin color.

　　Brief

　　1

　　People living in a particular

　　2

　　usually have the same skin color and there are many different skin colors in the world.

　　Reason for skin color The reasons for different skin colors mainly

　　3

　　in biology and history.

　　Biology reasons The amount of melanin, by which a person’s skin color is 4

　　, varies from people to people. The more melanin a person has, the 5

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