A small Southeast Asian snake has a surprising escape trick: rather than slithering away from danger, it rolls, reaching forward speeds of up to 3.69 meters per second, roughly four times faster than its top speed moving by ordinary side-to-side slithering.
Researchers at Toho University studying the dwarf reed snake, Pseudorabdion saravacense, found the animal rotates its body in a repeating cycle: one side rolls down toward the ground while a curved section near the head swings downward in what the team calls a "stroke." Which side touches down, and which direction the stroke swings, alternates with each cycle, producing continuous forward motion. The snake's body has no mechanical separation between its rotating trunk and its head, unlike a wheel on an axle, yet the head stays pointed in the direction of travel and holds a fairly constant height above the ground throughout, an effect the researchers found became more pronounced the faster the snake rolled.
"Keeping the head steady while the rest of the body rotates may help the animals maintain control," the researchers wrote in the study, published in Current Biology. The snakes were tested on a narrow track just 20 centimeters wide, suggesting the rolling gait may have evolved as a way to move quickly through the cluttered leaf litter and tight spaces of their forest floor habitat, where a longer, more exposed slithering retreat could leave them more vulnerable to predators.
