How did different skin colors come about

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how did different skin colors come about

Skin Color Quotes (33 quotes)

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Why Do We Have Different Skin, Hair and Eye Color?

How did different skin colors come about?

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.

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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. The actual skin color of different humans is affected by many substances, although the single most important substance is the pigment melanin. Melanin is produced within the skin in cells called melanocytes and it is the main determinant of the skin color of darker-skinned humans.

Skin Color Adaptation. Human skin color is quite variable around the world. It ranges from a very dark brown among some Africans, Australian Aborigine s, and Melanesians to a near yellowish pink among some N orth ern Europeans. There are no people who actually have true black, white, red, or yellow skin. These are commonly used color terms that do not reflect biological reality. Skin color is due primarily to the presence of a pigment called melanin , which is controlled by at least 6 genes.

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.

1 thoughts on “Skin Color Quotes (33 quotes)

  1. Human skin color reflects an evolutionary balancing act tens of thousands of years in the making.

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