Wind Tunnels in Pheromone Research

Abstract

During the dramatic growth in research on insect sex pheromones over the past 10 years, it has been demonstrated that both the chemical signal and the precopulatory behaviors exhibited by males and females are much more complex than originally thought. Chemical studies of sex pheromones have shown that, with few exceptions, females release a blend of several chemical components in a specific ratio and release rate. This specificity of the chemical signal is in part a result of the behavioral reactions of males under “natural” conditions: flight through space from a distance of several meters or more in shifting wind fields. Upwind progress in the plume of chemicals continues if the blend is that of a conspecific female, and the maintenance of contact with the plume is one of the most complex behavioral responses, involving visual feedback, a chemically modulated self-steered program of zigzags, and changes in linear velocity of flight, all performed as the insect samples the odor environment sequentially (Kennedy, 1983;Kuenen and Baker, 1983).