Many snakes seek shelter from the winter weather by holding up in dens. Sometimes hundreds of snakes will occupy the same den. Of the more than 2,700 different kinds of snakes in the world, only about 400 are venomous to some degree. All snakes are carnivorous. A snake's eyes appear cloudy several days before they shed their skin.
Snakes have backbones, just like human beings.
Their skeletal structure is composed of hundreds of vertebrae, with a pair of ribs to go along with each. Snakes flick their tongues in order to pick up chemical signals from their surroundings. Snakes do not have external ear openings.