CONTEXTUAL CHEMICAL ECOLOGY - MALE TO MALE INTERACTIONS INFLUENCE EUROPEAN CORN-BORER (LEPIDOPTERA, PYRALIDAE) MALE BEHAVIORAL-RESPONSE TO FEMALE SEX-PHEROMONE IN A FLIGHT TUNNEL

The responses of European corn borer, Ostrina nubilalis (Hubner), male s in a flight tunnel to sex pheromone, [11-tetradecenyl acetate (97:3, Z:E)] was dependent upon the context in which the males were exposed to the stimulus. Males, held individually in isolation before being ex posed to pheromone, flew upwind in the pheromone plume and landed on t he pheromone source significantly more often than males caged with oth er males before exposure to the pheromone. When groups of males were s imultaneously exposed to female sex pheromone, they responded, on a pe r-male basis, with significantly more upwind flights to pheromone and intense behavior near the pheromone source than did males exposed to t he pheromone individually. Heightened intensity of male response in gr oup flight was independent of whether the males were individually isol ated or caged with other males before being exposed to the pheromone. The enhanced behavioral output of males responding to pheromone in gro ups may represent an evolutionary adaptive advantage in instances wher e several males are simultaneously pursuing a single calling female.