Meeting Abstract
Jumping is essential for arboreal animals in behaviors such as capturing food and evading predators, but animals must jump from surfaces with different properties and orientations, like tree trunks, branches, leaves, or the ground. Different surfaces can impact the way that morphology and physiology interact with the environment to produce movement. We hypothesized that animals jumping from vertical surfaces would have lower performance compared with more horizontal surfaces because the changing orientation of gravity relative to the body would reduce the ability to effectively transmit force to the surface. We measured position, velocity, and acceleration from Cuban tree frogs jumping from surfaces at 45, 60, 75 and 90 degrees to test the prediction that jump performance would be greatest at 45 degrees and would decrease as the angle increased. We also measured jumps across a range of body masses to assess the impact of size on performance at different angles. Jump performance data was collected within a temperature controlled room from 29 frogs using a three-dimensional motion capture system in which a reflective infrared marker was used to track the frog through space. Contrary to our hypothesis, jump performance remained unchanged across all 4 angles and was unaffected by body mass. These results suggest that these arboreal frogs are well suited for these angles as they commonly experience them in nature. Future experiments measuring ground reaction forces may reveal the mechanism by which these animals overcome the challenge of the changing orientation of gravity relative to the body to maintain high jump performance.
