Essay about The Evolution of Human Skin Color

Animals fight for survival daily, and sometimes their lives depend on their ability to adapt with their surrounding environments. Natural Selection is the process in which individuals have certain traits that allow

Chimpanzees have what is called melanin, which is a dark brown pigment that protects them from UV radiation. Melanin is a natural sunscreen, which filters out UV radiation. It is been proven that people with high concentration of melanin in their skin heading to come from tropical areas and it has protected them from skin cancer. After all of this research, Jablonski and Chaplin then ask, “what role melanin might play in human evolution?” (170).

The skin colors differ because of the way evolution works. If you goto the sahara you will be expecting a lot more sun so vitamin D won't be as big as a problem unless you get to much, so people naturally evolved to have darker skin. While on the other hand the people living in the arctic evolved to have lighter skin to absorb more of vitamin D, this is because whiter skin reflects heat, but absorbs more vitamin D.

In what he called the ‘survival of the fittest’, Darwin suggested that through the process of natural selection animals with particular characteristics, as a result of possessing advantageous alleles, will survive. However, those with maladaptive genes cannot adapt to changes in environmental conditions, so will die or become extinct. Dowling (1994) stated that this process depends on three principles: species diversity, interaction and the spread of a species as a result of differential amplification. Sexual selection is another component of Darwin’s research, which explains the best strategies adopted for passing on genes to offspring. Moreover, there are problems with Darwin’s theory such as his attempts to generalise animal behaviour to the way in which humans interact in their environment. However, he has presented compelling evidence which is very scientific in its approach and methodology. Furthermore, contrary to Darwin’s evolutionary idea of survival of an individual, Dawkins (1976) suggested that the survival of the genes is more important.

Source: Figure obtained from the National Oceanic and Atmospheric Administration. Graph retrieved 18 October 2009 from http://www.cpc. ncep.noaa.gov/products/stratosphere/uv_index/gif_files/uvi_world_f1.gif. This U.S. Government material is not subject to copyright protection within the United States.

According to our reads, there is no biological evidence for race. But unfortunately for the last 500 years or so, people have been taught to except that just because our skin color and cultures might be different than each other, that we are “other”.

Every body has a different amount of pigment in their skin , that's how we are all different .

You are right, this quiz was indeed informative. I also think the theory that reference one’s skin tone to be darker or lighter due to the tropical, southern and northern states hold some level of validity. This theory sounds coherent to one of the effects of UV lighting contributing to melanocyte that produce and contain melanin. Melanin is any of a class of insoluble pigments, found in all forms of animal life, that account for the dark color of skin, hair, fur, scales, and feathers Furthermore, the fact that the human species originated from Africa and that we are subgroups of Africa is without question excited to learn and understand. Generally speaking, when I think about the race ideology behind European-American leaders in which they

Natural selection is considered one of the most important processes for a variety of species and the environment which allows the fittest organisms to produce offspring. To prevent a species from extinction, it is necessary for them to adapt to the surrounding environment. The species which have the ability to adapt to new surroundings will be able to pass their genes through reproduction. Within the process of natural selection, it is possible for the original genetic make-up of a species to become altered. The team will report on the different processes of basic mechanisms of evolution, how natural selection results in biodiversity and why biodiversity is important to continued evolution. The sources of genetic

A major function of melanin is to act as a defensive barrier of the skin against radiation damage. Ultraviolet light between the wavelengths 280-320nm (UV-B) causes sunburn and damages the skin on nonpigmented peoples. Exposure to this degree of light causes their skin to become dry, leathery, and wrinkled in appearance similar to that associated with aging. This can be seen in Whites living in Australia and South Africa, where ultraviolet light intensity is high because of the relative latitude or closeness to the equator.

We often connect ourselves to the world through our appearances. One of the first characteristics we notice about another human is the color of their skin. It is unavoidable, as the largest organ of the body, it covers and highlights our individual features and forms a protective wall against the elements. There is no escape from the social repercussions our pigmentation causes no matter what range of the very broad spectrum of color we fall into. I have never thought so much about the genetic and social evolution of skin and its properties until I read Nina Jablonski’s Living Color: The Biological and Social Meaning of Skin Color. This book encompasses, in great detail, how our skin has evolved, adapted and mutated throughout time and in what

The color of the skin of each person is determined by their heritage and melanocytes. Melanocytes are cells that produce melanin, a pigment that plays a fundamental role in protecting against the harmful effects of ultraviolet irradiation from the sun. Therefore, the geographic area where we live also has some involvement in the color skin. This means that people living near the equator (Ecuador), with intense UVB irradiation, have developed darker skin to protect them from the harmful effects of UVB irradiation . Instead, those living in the higher latitudes, closer to both poles, they get a clearer skin to maximize vitamin D production.

Another theory said that dark pigmentation developed to prevent the overproduction of vitamin D. Vitamin d is a nutrient needed in only small amounts of the body. It’s produce by a reaction that occurs in the skin upon exposure to uv rays or ultraviolet B radiation in sunlight. Sadly both were proven wrong. Thus it was thought that the evolution of dark pigmented skin came about as a protective mechanism in populations of people that are moving from environments with low UV rays to high Uv rays. Examples of this is the light to moderately pigmented ancestral North Indians who came to inhabit India and east Asians who populated South America.The color pigment skin depends on the amount of sunlight thus UV rays. Lighter skin pigment depends on the population in high latitudes,populations groups dispersing in these areas would receive less UV exposure thus allowing them to have lighter pigment. Dark pigment would prevent the production of sufficient levels of vitamin D, which is necessary for calcium absorption and healthy bone growth. Its deficiency has implicated diabetes , autoimmune diseases and viral bacteria

Natural selection does not create organisms that are perfectly adapted to their environment for various reasons. One constraint is the fact that the environment is always changing. Disturbances in the environment are often caused by human influences and natural ecological processes that change what traits are beneficial to the organisms in order to survive in their particular surroundings. In the article, "Adaptation, Plasticity, and Extinction in a Changing Environment: Towards a Predictive Theory", it states that, “the unusual rate and extent of anthropogenic alterations of the environment may exceed the capacity of developmental, genetic, and demographic mechanisms that populations have evolved to deal with environmental change” (Chevin,

In this chapter, the topics of natural selection and the struggle for existence. He makes the important point that these two concepts are intertwined, especially because the struggle for existence will eventually ‘weed out’ some organisms while those who have variations which are favorable for the environment will survive, adapt and pass on their genes to the next generation. He also highlights the role that the environment plays in the struggle for existence; a particular variation might let a species thrive in one environment but might be disadvantageous in another environment. In this way, the most useful adaptations for success in a particular environment is inherited by offspring and the less advantageous characteristic die out as organisms that possess them do. He also talks about the role of nature in the struggle for existence by citing the fact that events like natural disasters and even predator-prey relationships allow for the survival of some organisms,