Roles and effects of environmental carbon dioxide in insect life

Carbon dioxide (CO₂) is a ubiquitous sensory cue that plays multiple roles in insect behavior. In recent years understanding of the well-known role of CO₂ in foraging by hematophagous insects (e.g., mosquitoes) has grown, and research on the roles of CO₂ cues in the foraging and oviposition behavior of phytophagous insects and in behavior of social insects has stimulated interest in this area of insect sensory biology. This review considers those advances, as well as some of the mechanistic bases of the modulation of behavior by CO₂ and important progress in our understanding of the detection and CNS processing of CO₂ information in insects. Finally, this review briefly addresses how the ongoing increase in atmospheric CO₂ levels may affect insect life.