S1-4.5 Jan. 5 Role of antennae in insect flight control SANE, SP*; DIEUDONNE, A; DANIEL, TL; University of Washington, Seattle; University of Washington, Seattle; University of Washington, Seattle email@example.com
The antennae of flying insects perform multiple sensory functions. In addition to being the primary olfactory organs, antennae serve an important mechanosensory role during flight. For example, in the hawk moth Manduca sexta , we have shown that the antennae vibrate during flight and are thus subject to strong gyroscopic forces during aerial maneuvers. The resulting strain patterns experienced by the basal mechanosensors of the antennae follow gyroscopic forces on the antenna. Moreover, intracellular records from afferent neurons in the basal mechanosensory Johnston's organs show that they are maximally responsive within the frequency regime of these strain oscillations. Thus, antennal mechanosensors are capable of reporting the gyroscopic forces. Here we show that the mechanosensory input from the antenna is crucial for flight control. We filmed the flight patterns of hawk moths in a darkened chamber illuminated by infra-red light. The moths were subjected three experimental treatments: those with (a) intact flagella, (b) amputated flagella and (c) their flagella removed and reattached, Moths with amputated flagella were significantly more likely to collide with the walls of the flight chamber or crash during flight and unable to fly in a controlled and sustained manner. When their flagella were rejoined, flight control was largely recovered. These experiments provide additional evidence that antennae operate as gyroscopic sensors in four-winged insects, analogous to halteres in the two-winged insects.