As you learned in the video, non-human primates have light skin covered with fur; biologists hypothesize that the ancestors that humans share with other primates also had light skin colored with fur. As the human lineage diverged from that of other primates, fur covering most of the body was lost, and skin became darker. Briefly explain why the loss of fur was accompanied by selective pressure favoring darker skin in early humans.

The loss of fur is a protection mechanism for the epithelium that covers us, over the years this method of protection was replaced by the protection provided by melanocytes with their melanin, therefore people who had a low presence of melanin could not survive in the evolution.

Explanation:

The presence of melanocytes and melanin in the skin is what protects it against ultraviolet radiation, over time the human being was affected by solar radiation, thus being one of the causes of bipedalism.

In those humans where melanin is defective or a small number of melanocytes are more predisposed to suffer epithelial pathologies today.

Human evolution then led to hair loss and increased epithelial tonality, causing those who could not have this phenotypic quality to be extinct or deceased.