Why do snakes shed their skin?
Snakes shed their skin because their outer layer does not grow with them. Shedding lets them grow larger and also removes parasites and worn-out skin.
A snake's outer skin is made of keratin, the same material as human fingernails. As the snake grows, this layer becomes too tight and worn. A new layer forms underneath, and the snake rubs its nose against rough surfaces to break the old skin, then crawls out, turning it inside out like a sock.
Young snakes, which grow quickly, may shed every few weeks, while adults shed a few times a year. Before shedding, a snake's eyes often turn cloudy and bluish, because the scale covering each eye, called the spectacle, is also shed. During this time, snakes can see poorly and may act nervous or hide.
Signs of health
A healthy snake usually sheds its skin in one complete piece. Pet owners watch for incomplete sheds, which can be a sign of low humidity, poor diet or illness. A shed snake skin is often longer than the snake itself, because it stretches as it is removed.
Did You Know?
Lizards also shed their skin, but usually in patches rather than in one piece like snakes.