The Secrets of Sidewinders

Have you ever tried running on sand? It’s hard to do because your feet sink in. Moving across sand can be a struggle for many animals. But it’s no problem for sidewinders! These species of snakes live in deserts in North America, Africa, and the Middle East. They easily move their long bodies across the slippery sand.

Have you ever tried to run on sand? It’s hard to do because your feet sink in. Moving across sand can be tough for many animals. But it’s no problem for sidewinders! They’re a species of snake. They live in deserts in North America, Africa, and the Middle East. The snakes easily move their long bodies across slippery sand.

Snakes move in different ways. Mostsnakes slither forward by turning their heads left to right, bending their bodies in an “S” shape. The snakes press off hard surfaces and push themselves straight ahead.

Instead of moving forward, sidewinders move sideways. They lift sections of their body off the ground, “almost like feet,” Rieser says. The snakes can control how much of their body is touching the ground. That reduces the risk of causing the sand to shift beneath them and sliding down sandy hills.

To find out whether the sidewinders’ skin helps them move, Rieser and her colleagues examined the shed skin of three sidewinders. She then compared them with the shed skin of non-sidewinders.

Snakes move in different ways. Most snakes slither forward. They turn their heads left to right. And they bend their bodies in an “S” shape. The snakes press off hard surfaces. Then they move straight ahead.

But sidewinders don’t move forward. They move sideways. The snakes lift sections of their body off the ground, “almost like feet,” Rieser says. That helps prevent the sand from shifting beneath them. And it makes it less likely they’ll slip down sandy hills. 

Rieser studied the shed skin of three different sidewinders. She wanted to learn whether it helped them move. She compared the skins with those of other snakes. 

Snakeskin is made up of folds called scales. Under a microscope, the scales on the bellies of many snakes have tiny spikes pointing toward their tails. These spikes increase friction, a rubbing force, between the snake’s belly and the ground in one direction. That friction helps the snake grip the ground and push itself forward.

Many snakes that don’t live in sandy environments would likely not move well if they were on sand. The tiny spikes on most snakes’ bellies would not help, says Rieser. The snakes might even end up buried!

Snakeskin is made up of folds called scales. Under a microscope, tiny spikes can be seen on the scales on many snakes’ bellies. The spikes point toward the snakes’ tails. They add friction, which is a rubbing force, in one direction. It happens between the snake’s belly and the ground. That friction helps the snake grip so it can push itself forward. 

Some snakes don’t live in sandy areas. They likely wouldn’t move well if they were on sand. The tiny spikes on their bellies would not help, says Rieser. The snakes might even end up buried!

Up close, the sidewinders’ bellies look much different than those of the other snakes studied. Their skin has tiny circular pits. The pits produce equal friction in all directions. That keeps the sand from shifting and allows sidewinders to move quickly.

Rieser wants to learn more about how animals evolved to move in their natural habitats. She also hopes her research inspires new types of robots. “We could help robots move in challenging environments,” she says.

Up close, sidewinders’ bellies are different. They don’t look like those of the other snakes studied. Their skin has tiny circular pits. The pits produce equal friction in all directions. That keeps sand from shifting beneath them. It allows sidewinders to move quickly. 

Rieser wants to learn more about these animals. She wonders how they evolved, or change over time, to move the way they do? She also hopes her research inspires the creation of new types of robots. “We could help robots move in challenging environments,” she says.