Adrian Bejan | Snake locomotion, from Design in Nature

Aug 30, 2025

This video explains snake locomotion as part of the broader rhythm of animal movement, showing that even without legs, snakes follow the same principle of balancing difficulty and ease to move forward. Their motion comes from fish-like origins, adapted for land, where the whole body acts as a series of muscle-driven pushes. By examining how the body bends and presses at specific points, the explanation links snake movement to patterns in rivers, crawling infants, and skiing, highlighting that the theory of locomotion applies universally across different forms of life.

The movement of a snake is compared to a very long train winding through mountains, except that instead of locomotives pulling, the snake spreads muscular effort along its body. This creates a wave-like shape that leaves a sinusoidal trail, just like fish do when they move across wet sand. The similarities between these trails and meandering rivers suggest that snake movement is guided by pushing sideways against invisible boundaries, much like water pressing against a stream’s banks.
Seen from above, the snake’s body forms repeating S-shapes, but at ground level, you can notice that not all parts of the body touch the surface evenly. The snake lifts slightly and presses at selected “elbows,” generating forward motion by alternating contact points. This detail shows that movement relies on intermittent pushes rather than smooth sliding, making each part of the body both support and propel.
The crawling of infants follows the same rule. Before walking, babies move using their elbows and knees, applying pressure at specific spots while lifting their feet. This similarity emphasizes that locomotion is a universal rhythm of pushing and releasing, whether with legs, arms, or an elongated body.
In profile, the snake appears to create small air gaps between its body sections and the ground, proving that its movement isn’t a continuous drag but a pattern of lifting and pressing. These micro-adjustments reduce friction while providing thrust, much like other rhythmic movements, which balance effort with ease to keep moving forward.
The discussion relates this movement to skiing, where descending involves alternating pushes and directional changes that mirror the snake’s winding path. The term “slalom,” coming from Norwegian for descent, reinforces the comparison between human-designed movement and natural snake locomotion. This shows that whether in rivers, infants, snakes, or skiers, the pattern of alternating bends and pushes follows a consistent law of movement.

CONSTRUCTAL NEWSLETTER

Discussion about this post