Imagine hiking in a South Asian forest when you see something float slowly past you out of the corner of your eye. You turn to look; what do you expect to see? A large insect, a bird…
How about a snake?
The paradise tree snake, known scientifically as Chrysopelea paradisi, has long been known for gliding from high forest trees safely to the ground. Physicists have found the behavior difficult to explain for a creature with no wings or skin flaps to assist its descent.
Jake Socha, assistant professor of engineering science and mechanics at Virginia Tech, filmed a sampling of snakes gliding off of a 15-meter tower and believes he can now explain how the snakes avoid a fatal fall.
Different from the flying squirrel’s smooth glide, the snake thrashes violently through the air as it descends. The result is a reduction in fall speed from six to four meters per second and a reduction in glide angle. Like a plane going from a fast steep dive to a slow shallow descent, the snake experiences less force on hitting the ground and therefore survives the fall.
“The snake is pushed upward – even though it is moving downward – because the upward component of the aerodynamic force is greater than the snake’s weight,” Socha said in a prepared statement to the press.
UC Davis students with fears of snakes flying at their faces, fangs exposed, can remain calm; the species is limited to forests in South Asia.
– Amy Stewart
