Meeting Abstract

P2.161  Tuesday, Jan. 5  Lateral asymmetry in the kinematics of halteres during maneuvering flight of crane flies FOX, JL; MYHRVOLD, CA*; HOWELL, D; DANIEL, TL; University of Washington; Princeton University; University of Washington; University of Washington jessfox@uw.edu

The halteres of dipteran insects act as gyroscopic sensory organs for flight control. They are actively oscillated during flight and experience large inertial forces, including Coriolis forces that occur during body rotations. The mechanosensory cells at the haltere’s base are thought to detect these Coriolis forces, rapidly sending information about the body’s rotation to the central nervous system. However, little is known about the motions and forces that occur at the base of halteres during natural behavior. Previous simulations of haltere motion showed that body rotations result in elliptical or lemniscate tip trajectories. Additionally, visual input can affect haltere kinematics, with the potential for separate control of left and right halteres. To assess the consequences of natural free flight maneuvers to the kinematics of halteres, we captured high-speed video of the cranefly Holorusia in free flight. Using four cameras, we filmed 5 crane flies at 1000 frames per second for >300 ms, long enough to capture 3D kinematics over many wingbeats (~25 ms wingbeat period). We recorded natural body rotations (yaw, pitch, and roll) while simultaneously measuring the sweep and elevation angles of haltere during each wingbeat period. We found that the amplitude of the sweep angle was significantly different during wingbeats where yaw rate was high. Furthermore, despite previous assumptions that halteres move symmetrically, we found that the left and right halteres had different relative sweep angles. This suggests that control of the halteres could be lateralized, and in turn, the information entering the nervous system from haltere mechanoreceptors will also be lateralized.