The sight of a snake strikes fear in the hearts of millions of people. Fear of snakes, or ophidiophobia, is among the most common phobias. Snakes can crawl, burrow, swim and climb. Can you imagine if these slithering reptiles could fly?

Some actually can. More precisely, they glide or parachute in the same fashion as a flying squirrel, frog, lizard or fish.

University of Chicago biologist Jake Socha has been studying the gliding patterns and biomechanics of these airborne creatures. In the Aug. 8 issue of Nature, the sixth-year graduate student describes some of the aerodynamics of the Chrysopelea paradisi, or paradise tree snake - one of five snake species that are purported to "fly".

Socha found that the aerial behavior of this snake is unlike any other glider. It exerts remarkable control over the direction it takes, despite an apparent lack of control surfaces. For example, while in flight, the snake does not bank, or lean into, the turns like most other flyers.

"Most flyers use some kind of a banking technique," he said. Instead, the paradise tree snake turns as it undulates from side to side.

The Nature article, titled "Gliding flight in snakes," also describes the three-dimensional kinematics of gliding by the paradise tree snake. More specifically, the snake changes its undulation pattern while airborne: the amplitude, or height of the waves, is two to three times larger, and the frequency is one-third lower.

For the study, Socha videotaped and photographed various snakes taking off from a 33-foot-high tower in an open field at the Singapore Zoological Gardens. He positioned two video cameras to record in stereo, enabling the three-dimensional reconstruction of the head, midpoint and vent coordinates of the snake throughout its trajectory.

Socha found that C. paradisi prepares to take off by hangin
'"/>

Contact: Catherine Gianaro
cgianaro@uchospitals.edu
773-702-6241
University of Chicago Medical Center
7-Aug-2002