Exploitation of Intraspecific Communication Systems: Illicit Signalers and Receivers

Abstract

We review exploitation of intraspecific communication by illicit signalers or receivers, restricting coverage to examples in which the exploiter or exploited, or both, is an arthropod. Illicit signalers aggressively mimic the chemical, acoustical, or visual signals normally used by their victims in sexual or social communication. Cited examples include bolas spiders that mimic pheromone blends to attract male moths as prey and femme fatale fireflies that mimic the flashing pattern of other species of fireflies to prey upon the responding males. Illicit receivers gain access to resources by eavesdropping on intraspecific signals. For example, several species of predatory beetles respond to the aggregation pheromones of bark beetles to feed on them or their offspring, and some parasitic flies orient to the stridulation songs of orthopteran species. In some cases, functional intraspecific communication systems may have evolved to reduce exploitation by illicit receivers; for example, changes in signal characteristics could make the signaler less apparent to potential exploiters. With rare exceptions, both illicit signalers and receivers tend to exploit the intraspecific communication systems of a limited number of taxa, probably because the production or detection of species-specific signals often requires the evolution of specialized signaling mechanisms or sensitive receptors. To convincingly demonstrate exploitation of intraspecific communication, one must first decipher the signals and responses that are part of the communication system. To date, the intraspecific communication systems of a few taxa (e.g., Lepidoptera, fireflies, crickets) are reasonably well understood, but those of many other groups are unknown or poorly understood. Even with this limitation, it is clear that exploitation of these systems by illicit signalers and receivers is widespread and diverse.