A whole body doing the work of feet
How Does a Snake Move With No Legs?
A snake pushes against every bump and pebble it can find, using several hundred pairs of ribs.
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Step 1 of 5
It pushes sideways to go forwards.
A snake throws its body into curves and presses the outside of each curve against stones and stems. Every push is sideways, but the sideways pushes add up to travel straight ahead.
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Step 2 of 5
The belly scales only grip one way.
Look underneath and the scales are wide plates with their back edges free. They slide easily forwards and catch when pulled back — like the hairs on a ski, so the snake only slips the useful way.
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Step 3 of 5
Ribs do what legs do.
A snake can have several hundred ribs, and each pair has its own muscles. So the body is not one long tube — it is hundreds of small movable sections, controlled a few at a time.
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Step 4 of 5
It smells with its tongue.
The flick brings scent particles back to two pits in the roof of the mouth. Because the tongue is forked, the two tips sample slightly different places — so a snake smells in stereo and knows which way to turn.
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Step 5 of 5
The jaw is not locked shut.
A snake's lower jaw is in two halves joined by stretchy tissue, not fused like yours. The halves walk over a meal one at a time, which is how a snake swallows something wider than its own head.
A snake does not 'unhinge' its jaw. Nothing dislocates — the two halves were never joined tightly in the first place.
The short version
A snake travels by pressing curves of its body against the ground, with one-way belly scales and hundreds of rib pairs doing the pushing.
Try it yourself
Lie on a smooth floor and try to move without using arms or legs. Now do it on a rug. The grip is the whole trick.
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