Meeting Abstract

57.5  Thursday, Jan. 6  Functionality of Wings in Flight and Gliding of Stick Insects ZENG, Y*; DUDLEY, R; Univ. of California, Berkeley; Univ. of California, Berkeley dreavoniz@berkeley.edu

Many unresolved questions in animal flight evolution relate to the transition between flightless and volant forms. Functional analysis of transitional modes using anatomical intermediates may help to assess biomechanical underpinnings to the origin of insect flight as well as multiple origins of derived flightlessness among winged insects. The stick insects (Insecta: Phasmatodea) exhibit tremendous diversity of wing morphology and frequent evolutionary transitions between full flapping capacity and flightlessness. Through a combination of lab and field work, we systematically studied the wing morphology in stick insects and their roles in various flight and gliding modes. The morphological correlates of various wing morphs and their kinematics in flight were quantitatively investigated. Comparison among multiple flight and gliding modes suggests a transitional pattern in wing morphology coupled with kinematics, e.g. stroke amplitude and wing rotation, whereas the relative aerodynamic contributions from wings and other body parts determine the overall flight trajectory, stability and maneuverability. The adaptive significance of gliding flight performed with miniaturized wings is clear for an arboreal context, where the selective advantages of winglets may help to understand the possible evolutionary transitions between flightless and volant forms.