The Body: A Guide for Occupants

by Bill Bryson

“The loss of most of our body hair and the gain of the ability to dissipate excess body heat through eccrine sweating helped to make possible the dramatic enlargement of our most temperature-sensitive organ, the brain.” That, she says, is how sweat helped to make you brainy.

Itching (the medical term for the condition is pruritus) is confined to the outer layer of skin and a few moist outposts—eyes, throat, nose, and anus primarily. No matter how else you suffer, you will never have an itchy spleen. Studies of scratching showed that the most prolonged relief comes from scratching the back but the most pleasurable relief comes from scratching the ankle.