expectancy of women due to birthing problems. Children may have been born brain damaged due to deliverance through a deformed pelvis. Children and adults with painfully weak bones and muscles or stunted growth would be disadvantaged for their type of environment. In short, the early African migrants in northern latitude such as Europe may have experienced high child mortality rates and low life expectancy because of a vitamin D deficiency caused by lack of sunlight. Vitamin D deficiency may have had considerable evolutionary significance due to major selection occurring in the population of Africans in Eurasia. Dark-skinned individuals and even light-skinned individuals who covered themselves with clothing may have been selected out. The only individuals who survived were those with very low or no pigmentation such as albinos. Albinism is due to mutations that affect the function of the enzyme responsible for the production of melanin, causing the absence or extremely low level of pigmentation. Present-day populations of Homo sapiens reflect a thorough mixture of assorted genetics due to gene flow, selective pressures, drift, and random mutations. Environmental pressures such as ozone depletion and global warming may be the selective pressures of the future. Ozone depletion will increase the ultraviolet radiation and cause major problems for light-skinned individuals. Modern technology such as vitamin supplements and sun block creams have allowed individuals to stay healthy in many parts of the world, causing the adaptive qualities of skin and hair pigmentation to be minimized. In conclusion, melanin production has played a considerably important role in human evolution. Not only does it influence color pigmentation through its protective role of defending against harmful UV rays, but also determines detrimental features such as eye-sight and hearing. Furthermore, melanin production and its evolutionary adaptions mark an impo...
