Human variation
The popular idea that northern European developed light skin has brought about a major debate by most researchers. Rapping up of the skin capacity to capture UV light is indeed significant. However, it is seen that changes in the skins function act as a barrier to the elements, thus making a greater contribution to the alteration in skin pigment in northern European latitudes.
According to the law of natural selection, humans moved to a hot open environment to obtain food. There was an adaptation, including an increase in the number of sweat glands and, at the same time, reducing the body hair amount. However, melanin is a brown pigment that reduces UV light; thus, it brings an understanding that people in the northern latitude developed a lighter skin color due to less sunlight reaching the area. As individuals migrated from places far away from the equator, natural selection allowed UV rays to penetrate and produce the essential vitamin D. This shows that the idea of natural selection is based on the locations where the ancestors lived and how strong the sun was in that particular region.
Due to natural selection, most of the individuals who survived the adaptation remained due to the survival theory for the fittest. Thus, it is significant to note that the individuals who had favorable characteristics, including the attraction to lighter skin, bred and passed their alleles with favorable characteristics to the next generation in the northern latitude. This occurred due to a change in the phenotypic composition of those who had migrated to the north. There was a change in the genetic pool frequency leading to evolutionary changes and a rise of new species in the north who had lighter skin than the previous generation due to stabilization selection and speciation.
References
Beth Shook, Katie nelson, Kelsie Aguilera, and Lara Braff explorations: an open invitation to biological anthropology. American Anthropological Association Arlington, VA 2019