Active Behavior and Reflexive Responses: Another Perspective on Odor-Modulated Locomotion

Abstract

That male moths orient their flight into the wind upon sensing wind-borne pheromone from a conspecific female, and modulate their subsequent flight performance with respect to pheromone and wind stimuli, is generally accepted by most that study this behavior (see Baker and Vickers this volume; Kramer, Carde and MafraNeto this volume; and Witzgall this volume). The behavioral and physiological mechanisms that enable a male moth to accomplish this complex feat are still a matter for considerable (and lively) debate. As we initiated our approach to this behavior from an explicitly neuroethological perspective (see Arbas this volume) using the moth Manduca sexta as our model, we decided that, rather than assume all male moths locate pheromone sources using the same mechanisms, we would start “from scratch.” This approach has forced us to examine our data in new and different ways and, at times, to come to conclusions and propose mechanisms that are at odds with some of the currently accepted views of the control of pheromone-modulated flight in moths (Arbas and Willis 1994, Willis and Arbas 1994). However, careful review of the work of earlier researchers in this field, especially that of J.S. Kennedy, has revealed hints of many of the interpretations that we have come to with regard to our own data. In order to proceed in the development of our own ideas regarding the generation and control of this biologically and agriculturally interesting behavior, it has been critical to clearly understand the existing hypotheses.