Skin Color Quotes (33 quotes)
How Did Skin Color Evolve?
Human skin color can vary from almost translucent to almost black. This range of colors comes from the amount and type of a pigment called melanin found in the skin. There are two types of melanin--eumelanin and pheomelanin. In general, the more eumelanin in your skin, the darker your skin will be. People who make more pheomelanin than eumelanin tend to have lighter skin with freckles.
Take a look around you. Look at the people in your neighborhood. Look at the kids in your school. Take notice of the people around your town, at the mall, in church, and at sporting events. What do you notice?
Most people associate Africans with dark skin. But different groups of people in Africa have almost every skin color on the planet, from deepest black in the Dinka of South Sudan to beige in the San of South Africa. Now, researchers have discovered a handful of new gene variants responsible for this palette of tones. The study, published online this week in Science , traces the evolution of these genes and how they traveled around the world. While the dark skin of some Pacific Islanders can be traced to Africa, gene variants from Eurasia also seem to have made their way back to Africa.
Human skin color ranges in variety from the darkest brown to the lightest hues. An individual's skin pigmentation is the result of genetics , being the product of both of the individual's biological parents ' genetic makeup, and exposure to sun. In evolution, skin pigmentation in human beings evolved by a process of natural selection primarily to regulate the amount of ultraviolet radiation penetrating the skin, controlling its biochemical effects.
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The most obvious of these is skin color. Many see this as a reason to doubt the Bible's record of history. They believe that the various groups could have arisen only by evolving separately over tens of thousands of years. However, as we shall see, this does not follow from the biological evidence. We know that skin color is governed by more than one pair of genes. For simplicity, let's assume there are only two, 1 located at positions A and B on the chromosomes.
Why do people from different parts of the world have different colored skin? As early humans moved into hot, open environments in search of food and water, one big challenge was keeping cool. The adaptation that was favored involved an increase in the number of sweat glands on the skin while at the same time reducing the amount of body hair. With less hair, perspiration could evaporate more easily and cool the body more efficiently. But this less-hairy skin was a problem because it was exposed to a very strong sun, especially in lands near the equator. Melanin, the skin's brown pigment, is a natural sunscreen that protects tropical peoples from the many harmful effects of ultraviolet UV rays.
Skin color can be everything from very pale to very dark, and many shades in between. That's because of something called melanin, which is made in the epidermis. Some people call it pigment. Because people with darker skin have more melanin, they usually don't get as wrinkly when they get older. They're also less likely to get skin cancer.