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Skin Color - Evolutionary Adaptation

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Scientists have found that through the evolutionary process, humans have lost the ability to produce dense amount of hair. This results in a mostly naked body, much more susceptible to the taxing effects of UV rays. There to be more dark skinned folks closer to the equator as well as lighter skinned people closer to the poles; this happens in effect from the preceding populations with favorable traits according to their environment surviving do these characteristics get passed on (Jablonski and Chaplin). Thus the evolution of humans over time shows that because of the environmental factors that contribute to or reduce the likelihood of the survival of certain species, that population has gone through natural selection to accommodate to their ecosystem such as through the improvement in the efficiency of absorbing Vitamin D and having variations of skin color. There is a chain of events that leads scientist to believe that skin pigmentation has been an adaptation for humans transcending the generations. So as to compensate for the loss of the hair protection, because as humans we no longer needed hair after the significant cool down of the earth, primates developed “a dark-brown pigment melanin in response to UV radiation” (Jablonski and Chaplin). This protection is useful because UV rays are shown to destroy melanocytes due to over exposure to sunlight, resulting in a cancerous melanoma. So those that benefit the most from a mutation such as the change in pigmentation in the skin would be the populations nearer to the equator because they are more susceptible to direct UV ray sunlight. Folate acid “is essential for the synthesis of DNA in dividing cells [and] rapid cell proliferation” (Jablonski and Chaplin). In essence, this is important because this plays a key role in the wellbeing of the next generations. It can be seen in tests done to mice that when there is a lower level of folate, there is a higher level of infertili

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