This image below is showing a female with different colors of the skin. Now, can you detect the rightful color of the woman’s skin? I am sure you can’t! This shows that we are all the same in spite of our skin color. After all, the DNA of any two humans is 99.97 percent identical.

Image courtesy of Nancy Burson/The Human Face, The Human Race Machine and Truth.

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“The more we recognize our selves in others, the more we can connect the human race”
Nancy Burson

"We may have different religions, different languages, different colored skin, but we all belong to one human race."
Kofi Annan

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Have we not wondered sometime in our life why humans have different skin colors? If you have children they might have even asked this same question or is yet to ask when they recognize this difference amongst people. So, some possible answers that you might have used to explain this could be: You got your color from- our relatives (ancestors); the sun; our genes and/or from melanin that is in our skin. If you have used anyone of these answers to explain skin color then, you are on the right track. As a matter of fact, all the possible answers given above do play an active role in the color of skin we have. Now, we are going to look at how these answers are related and what role they play in the color of our skin.


Our skin color is determined(colored)by the pigment called melanin (meh-luh-nin).Melanin,dark brown or black in color,is produced by special cells called melanocytes (mel-AN-o-sites) located under our outer layer of skin. The function of melanin is to protect our body (skin)from harmful sun rays called Ultraviolet radiation. Ultraviolet radiation from the Sun can cause chemical changes in our cell tissue which can then lead to skin cancer. Melanin protects the skin by absorbing the harmful Ultraviolet radiation (UV), acting as a sunscreen. It also neutralizes free radicals, which are harmful chemicals that form in the skin after being damaged by ultraviolet radiation. This therefore means, the more melanin we have, the better the UV protection we have against the harmful radiation from the Sun’s rays. Likewise, the amount that we have in our skin determines how light or dark our complexion will be. This means, People with light (fair) skin will have just a little melanin while those with Darker skin will have much more melanin present. For those with yellow skin tone, this is determined by another pigment called carotene, a yellow pigment.

A person who spends a lot of time in the sun, their skin will become darker since the melanin in the skin gets more active producing more of this pigment to reduce the harmful UV effects of the sun. This same principle is used in tanning.How much of this pigment we have is also determined by the genes we inherit. Genes ( short pieces of DNA) are units of information inside the cells of our body. Genes make up the blueprint, or plan, for the human body and its functions. It is therefore through our genes that traits are handed down from parents to offspring, in a process called heredity. In other words, this is what is responsible for our genetic makeup (genotype).


How do we explain this genes with the color of our skin and our ancestors? Early humans (hominids) that originated and lived in equatorial Africa had a coat of hair that covered their entire body that protect them from the Sun’s harmful UV. After hundreds of thousands of years our early primate ancestors started to evolve (evolutionary processes) and hair production diminished leaving them their light skin exposed to the Sun’s ray that provide minimal protection. This therefore means a fair skinned person living near the equator is susceptible to several health risks, such as skin cancer (melanoma). On the other hand, a person with darker skin meant greater protection and therefore had a greater survival advantage. Thus, a process called Natural selection , filters out certain parental genes (those for lighter skin) in successive generations, producing offspring with slightly different characteristics and less genetic variability. Consequently, lighter skin persons in comparison to those with darker skin had to a lesser degree less chance of living to reproductive age and passing on their genetic trait (genes) for light skin color to their offspring. Parents with dark skin then have children with dark skin. Over time, persons with darker skin became a dominant feature in Africa. This allows successive generations to adapt to their environmental changes carrying only the genes that are necessary for survival of the fittest. This prevents the extinction of the human race.

However, some of these early humans eventually migrated from the equatorial region Africa and settled in areas of Asia and Europe (closer to the poles). Here the northern climate is much cooler due to the fact that radiation from the sun becomes much less intense especially, during the winter season where this was even further weakened. As a result, because radiation from the sun was less intense, their melanin production gradually decreased to allow acclimation to the climates. This therefore means a dark skinned person living in polar latitudes will gradually evolve into people with lighter skin color such as white. In comparison to the equatorial climate where too much UV light pose serious health risks such as skin cancer, likewise too, little UV light can also be seriously harmful to our health. The reason for this is that, UV light is necessary for our bodies to make vitamin D which forms in the skin when exposed to sunlight. Vitamin D is required by the human body in order to build strong bones. Therefore this means a dark skinned person living near the poles is susceptible to health risk such as vitamin D deficiency which cause the disease called Rickets. Absence of vitamin D produces rickets. This is due to the fact that they have much more melanin in their skin than those with fair skin which means greater screening protection from the limited UV radiation and therefore lowering their survival advantage. Thus, the opposite will happen when compared to what happened in Africa. Natural selection will filter out parental genes for darker skin in successive generations, producing offspring with slightly different characteristics (lighter skin, eye color) and less genetic variability ( a white population). Consequently, darker skin persons in comparison to those with lighter skin had to a lesser degree less chance of living to reproductive age and passing on their genetic trait (genes) for dark skin color to their offspring. Parents with light skin then have children with light skin.

Over time (approximately 10,000 years) persons with dark skin gradually evolved into people with lighter skin color such as white. This type of skin color then became dominant in Europe and Asia. This, as mentioned earlier, allows successive generations to adapt to their environmental changes carrying only the genes that are necessary for survival of the fittest. For many generations, dark-skinned people lived near the equator and light-skinned people tend to live at the higher latitudes.

Now, in modern time, man has been moving around the entire globe, visiting, working and living in these different countries of different climatic conditions with a population of people of all skin colors. All of this is made possible by the modern knowledge we have in science and technology. People can travel freely and live in other countries without being harmed because one skin is too light or too dark. You can now: take supplements of vitamin D, travel in cars, trains, planes, ships, wear protective clothing for the appropriate weather climatic conditions, wear sun screen lotion to help protect skin from UV, live in better and safer houses from weather conditions, have access to better medicine, have more knowledge about the enviroment and the world at large and so on.

Now you should be able to explain why some people living closer to the poles are light skinned people with blond hair and blue eyes, while people living near the equator have black skin, black eyes, and black hair. So, if your relatives from a long time ago lived in a location where it was very sunny (close to the equator) then you are more likely have dark skin. And if your relatives from a long time ago lived in a location where it was very cold (close to the poles) then you are more likely have light skin. Offspring will therefore be the same skin color of their parents. Through migration you will now have dark skin persons living in countries closer to the poles and light skin persons living in countries closer to the equators. Hence, people coming together from different sections of the globe will produce offspring with various hues and degrees of pigmentation found in the skin of humans. This varying spectrum of colors are directly related to the distribution melanocytes cells that make the pigment melanin.


Did You Know?:

• Freckles and moles, which occur in people of all races, are small, concentrated areas of increased melanin production.

• Albinism is a condition in which an animal (such as a human ) is incapable of producing melanin. People with albinism have little or no pigment in their eyes, skin, or hair. They therefore appears white with pink eyes.

• Melanin: Found in feathers, scales, cuttle ink, human skin, hair, fur, choroids coat of the eyes, in cellular immune responses, wound healing in arthropods, the substantia nigra of the brain and various tumors.

Quotes On Skin Color

We judge on the basis of what somebody looks like, skin color, whether we think they're beautiful or not. That space on the Internet allows you to converse with somebody with none of those things involved.
Bell Hooks

The colour of the skin is in no way connected with strength of the mind or intellectual powers.
Benjamin Banneker

Color is an inborn gift, but appreciation of value is merely training of the eye, which everyone ought to be able to acquire.
John Singer Sargent

"We may have different religions, different languages, different colored skin, but we all belong to one human race."
Kofi Annan

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