Concertina movement

From Freepedia

Concertina movement is the movement occurring in snakes and other legless organisms that consists of gripping with portions of the body while pulling/pushing other sections in the direction of movement. There is no continuous posterior propagation of the static portion, and movement is irregular, with parts of the snake alternately stopping and moving. This movement appears to be quite strenuous and slow compared to other methods of locomotion, but no scientific studies have been published yet on the energetics of this form of motion, and the only kinematic study focused exclusively on its use to move through tunnels. Studies on arboreal concertina locomotion are currently underway. One of the most efficient types of movement for attacking prey.