In contrast to other animals, humans sense their world chiefly by vision, sound, and touch. We have, in general, a remarkably undeveloped sense of smell, and so it is not surprising that we fail to appreciate how important chemical signals are in the lives of other organisms. Chemical signals and cues serve insects in numerous ways, including sexual advertisement, social organization, defense, and finding and recognizing resources. Chemical ecology seeks to identify these chemicals and to establish how they affect an organism's behavior, physiology, and interactions with other organisms. As the techniques to identify fully the structures of natural products have become increasingly sophisticated and powerful, the amounts of natural products needed for characterization have diminished, and the number of identified compounds that mediate behavioral and physiological interactions has proliferated. Our understanding of precisely how organisms employ such chemical information, however, continues to lag behind our ability to characterize the chemicals involved. It is also clear that the discoveries to date represent a miniscule sampling of the multitude of insect species that use information conveyed by chemical signals and cues.

These reviews are designed to provide in-depth overviews and syntheses of defined areas in the chemical ecology of insects and their closely related arthropods. The topics covered in this volume include: chemical defenses of plants against insect herbivores; floral odors mediating insect pollination; how parasitic wasps use odors emitted by herbivores and the plants on which they are feeding to find their herbivore hosts; semiochemicals of mites; pheromones of spiders; pheromones of cockroaches; the intricate defensive and pheromonal relationships between arctiid moths and chemicals from their host plants; and the selective forces that structure moth communication by pheromones.