The air is not the domain of winged beasts alone. Some creatures¿certain species of squirrels and lizards among them¿glide above the ground with the help of paired skin flaps that generate lift. But in the case of the paradise tree snake (right), which dwells in the tropical rainforests of South and Southeast Asia, no such appendages exist. Nor, for that matter, do any other morphological specializations. Yet the animal "flies" with great precision. Study results published today in the journal Nature reveal how.

Videotapes and photographs of wild-caught snakes gliding from a 33-foot-high tower to the ground at the Singapore Zoological Gardens reveal that the animal first dangles from a branch and loops its body into the shape of a J. It then launches itself into the air by accelerating up and away from the branch, and flattens its body to nearly twice its normal width. This, in combination with aerodynamic undulating, allows the snake to stay aloft. Harder to discern is how the beast can do both at once. According to University of Chicago graduate student John J. Socha, who conducted the research, "whatever muscles it¿s using to flatten are probably decoupled from the muscles it¿s using to undulate." This, he surmises, probably requires specialized neuromuscular control.

The snake is surprisingly adept at aerial maneuvering, Socha observes. From the tower it can travel up to 70 feet, make roughly 90-degree turns and it always seems to land unharmed. Exactly why these limbless reptiles take to the air in the first place is not known, but their fellow gliders do so to travel more efficiently, pursue prey or evade predation.