In the May 15, 2005, issue of the Journal of Experimental Biology (http://jeb.biologists.org/content/vol208/issue10/), scientists described the effects of size and behavior of flying snakes, and found that the smaller animals were better gliders.

"Despite their lack of wing-like appendages, flying snakes are skilled aerial locomotors," said lead scientist and author Jake Socha, Ph.D., who has been studying these unique creatures for the past eight years.

With the help of colleagues Michael LaBarbera, professor of organismal biology and anatomy at Chicago, and Tony O'Dempsey, an expert in photogrammetry, Socha used 3-D flight information from the synchronized recordings of two video cameras to digitally reconstruct the trajectories, speed and body postures of Chrysopelea paradisi, or paradise tree snake, and Chrysopelea ornata, golden tree snake.

In this study, Socha, who also is a biologist at Argonne National Laboratory, found that paradise tree snakes are true gliders, traveling further horizontally than dropping vertically. The best flight Socha recorded traveled 13 degrees from the horizon at the end of its trajectory.

Socha correlated 19 performance variables, such as glide angle and horizontal speed, of the snake's flight with 16 size and behavior variables, such as mass and snout-vent length, of the animal's body. He found that body length and wave amplitude are important predictors of flight behavior, but wave frequency was not.

"These high-amplitude undulations visually dominate the behavior, yet their frequency is unrelated to the snake's glide performance," Socha said.

So why do they undulate? Socha and LaBarbera suggest it's for stability. Just as a person who makes small balancing adjustments while wal
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Contact: Catherine Gianaro
catherine.gianaro@uchospitals.edu
773-702-6241
University of Chicago Medical Center
11-May-2005