Meeting Abstract

P3.143  Friday, Jan. 6  The Effect of Asymmetric Morphology in the Aerial Righting of a Larval Stick Insect LAM, K*; ZENG, Y; DUDLEY, R; Univ. of California, Berkeley; Univ. of California, Berkeley; Univ. of California, Berkeley kenrickcl@yahoo.com

The mechanism by which invertebrates aerially right themselves has only recently been elucidated. Our previous work with a larval stick insect (Extatosoma tiaratum) has shown that when released upside-down, the righting reflex initiates immediately after the loss of contact. Such righting behavior is characterized by a simultaneous, bilateral symmetrical dorsiflexion of the legs, forming a shuttlecock-like body geometry that enables a 180 degree turn through aerodynamic torque. In this work we further investigated such passive righting mechanism by studying how asymmetry in leg morphology may affect the performance. The mass, surface area and length of legs were experimentally manipulated in larval stick insects. With high-speed filming and analyses based on three-dimensional reconstructions, we compared the kinematics and aerodynamic properties of righting performance in insects with different treatments. Our results may help understand the importance of morphology in the basic aerial maneuvers of invertebrates.