P3.136 Thursday, Jan. 6 Olfactory modulation of pre-flight shivering behavior in male moths CRESPO, J.G.*; GOLLER, F.; VICKERS, N.J.; University of Utah, Salt Lake City; University of Utah, Salt Lake City; University of Utah, Salt Lake City firstname.lastname@example.org
In nocturnal moths olfaction is the predominant sensory modality shaping many of the adult animal’s activities, including reproduction. A two-component pheromone blend is sufficient to elicit the typical zigzag upwind flight behavior in Helicoverpa zea males. However, before flight can be initiated, the endothermic flight muscles must first be warmed-up by shivering. We investigated the influence of olfactory sensory input on this thermoregulatory behavior. An infrared camera placed above a small wind tunnel was used to record and measure the thoracic temperature changes in free animals that were exposed to odor blends varying in their composition (ranging from an attractive pheromone blend to an unattractive blend containing behaviorally antagonistic odorants). In addition, maximum vertical force per unit muscle mass as a function of thoracic temperature was determined in tethered flight with a force transducer. Male H. zea exposed to the attractive pheromone blend spent less time on the ground when shivering, warmed up at faster rates and took off at lower mean thoracic temperatures than those males exposed to other pheromone blend combinations. Force measurements demonstrated that these lower thoracic temperatures exhibited by males exposed to the attractive pheromone blend, correspond to low maximum vertical force production when compared to the other treatments. Since there is an optimal thoracic temperature for flight, these results indicate that male moths are prepared to compromise optimal flight efficiency with the possibility of being the first to arrive at a receptive female. Supported by NSF grant IOB-0416861 to NJV.