Humans and chimpanzees have about the same number of hairs on their bodies,
but human hair is finer and harder to see.

A chimp has no more individual hairs than a human. While the texture of the
hair on the human body is much finer and less visible to the naked eye, it
is actually about the same amount of fur as on a chimp. It is thought that
perhaps humans originally had a thicker coat of fur that may have served as
protection, but it eventually receded over time as it began to be less
necessary for survival. Evolutionary theories as to why humans’ body hair
became finer include making it easier to sweat, as well as to make
parasites and lice less of a nuisance.