How do snakes move without legs?

Snakes have evolved several specialized methods of locomotion to overcome the absence of limbs, utilizing their body musculature and ventral scales to interact with their environment.1

• Serpentine Locomotion: The most common method, where the snake forms S-shaped loops and pushes against environmental resistance like rocks or twigs. This is also how snakes swim via lateral undulation.1
• Concertina Locomotion: The snake anchors its tail and posterior body, extends its head and forebody forward, then pulls the rear portion up in accordion-like folds to repeat the cycle.1
• Rectilinear Locomotion: Used by heavy-bodied snakes, this method involves moving in a straight line. Muscles move the ventral scales in a sequence of lifting, anchoring, and pushing, which inches the body forward.12
• Sidewinding: Primarily used in desert environments, the snake lifts its body in loops and shifts them laterally, moving sideways to minimize contact with hot sand.1

These diverse techniques allow snakes to navigate varied terrains, from branches to shifting sands, by effectively managing friction and leverage.1