Snake Locomotion

Since snakes lack limbs locomotion is very different to most other vertebrates. Locomotion is produced by different types of movement based on absence or presence of contact between the animal's body and the medium through which the snake is moving. Most species can use different types of locomotion but some species are specialised and use only one.

Lateral undulation

Lateral undulation is the type of locomotion usually associated with snakes i.e. side to side wriggling. At any given time various areas of the snake’s body are pushing simultaneously against a number of fixed points. As the snake moves forward new contact points are made. This is identical for movement across desert, through branches or swimming.

Concertina locomotion

This is common in burrowing snakes and can be seen when a snake crawls through a tube. While the back half of the body acts as an anchor the front half is pushed forward. The back half is then drawn forward.

Rectilinear crawling

The edges of the scales act as anchor points and the muscles then pull the body up to that point. This is often used by large snakes.

Sidewinding

This is similar to concertina locomotion but the angle of movement is at 45 degrees to the direction that the snake is pointing.

• For information concerning snake physical examinations, see here