Meeting Abstract
Natural habitats present gliding organisms with various challenges to negotiate as they move from one location to another in air. The glide target and execution may vary with behavior like seeking mates, avoiding predation, territorial aggression or foraging, and consequently determine the glide distance. Longer glides (L) require the animal to generate lift for a sustained duration and increase the probability of encountering obstacles in a cluttered environment. Shorter glides (S) may reduce the search area for mates and food but allow more careful selection of a landing site. Quantifying voluntary glides in a natural setting may provide insight into the outcomes of behavior on decision making and glide execution. We recorded short (< 4m) and long voluntary glides in a wild, freely-behaving population of the flying lizard Draco dussumieri and extracted kinematic profiles using 3D tracking (n=30). We identified three distinct glide phases – ballistic takeoff, glide and landing. Results indicate similar glide execution for short and long glides. The duration of the ballistic dive phase was comparable (t(S)=0.37 ± 0.05 s, t(L)=0.36 ± 0.06 s), with higher velocity and steeper descent angles in L compared to S. Extended glide and landing phases were seen in L with higher maximum velocities (v(L) ~6.65 ms-1, v(S) ~4.89 ms-1) and lateral maneuvering. We identified peaks in centripetal force during L which correspond to turns undertaken during the glide phase. Lastly, a linear relationship was found between the glide distance and the corresponding height lost. These results suggest that the decision to execute a short or long glide is made before or shortly after takeoff. However, the possibility still exists that short glides could be extended to long glides allowing the lizard to achieve higher velocities to facilitate maneuvering.
