How Our Hair Knows Its Length

Why don’t my leg hairs grow to be a foot long?

Funny how we’ve lost most of the hair on our bodies, yet we obsess so much about the strands that remain… Photo by kyle smith on Unsplash

Humans, unlike apes and our other closest species relatives, are relatively hairless. This is largely accepted to be an adaptation to moving away from shady forests and out into the open savannah, where less hair allowed us to better regulate our temperature through sweating.