Sheep

A sheep's rectangular pupils give it close to 300 degrees of vision without turning its head — useful for an animal whose main defense is noticing trouble early and moving as a group. They're shorn once a year in spring, a haircut that yields several pounds of wool per animal and leaves them looking about half their previous size. Sheep recognize and remember individual faces, both of their flockmates and of the people who feed them, for years at a time.