What is the point of butt hair?

Answer 1

Body hair really doesn't have a function in modern humans, but it probably did at some point in the ancient past of our species. Humans are mammals, and mammals in general are covered with body hair. This hair (or fur) provides protection from weather elements, as well as from physical damage such as cuts and abrasions. For whatever reason, humans as a species have genetically lost most of their body hair. Most that remains is residual and mostly confined to the head and groin, and to the facial region of most mature males; we know that genetics are involved because there are individuals with far more body hair than usual, and because the tendency toward body hair runs in families. ---- Whilst most of what you say is reasonable, in fact humans have the same number of hair as apes for example, about five million of which two percent are on the scalp. It is just so fine that it is hardly noticable although it covers our entire body. The areas where it is thickest are around parts where friction occurs and on top of the head for protection.