Ecological differentiation, interference, and coexistence in Odonata

Recent work in coexistence theory has begun to more fully consider the diverse factors that may foster or retard species coexistence and the spatial scales over which this may occur. This chapter considers how ecological differentiation and interference may influence coexistence in Odonata. Studies of ecological differentiation have revealed how resource competition and predator-prey interactions may foster species coexistence, but they have also revealed evidence of neutrality among co-occurring odonate species. Both niche and neutral processes may simultaneously shape odonate assemblages, which can arise locally as well as regionally among different populations. Common forms of interspecific interference in Odonata include intraguild predation at the larval stage, and aggression (e.g. territorial fighting) and reproductive interference (e.g. attempted mating) at the adult stage. Currently, more is known about the evolutionary effects of interference between co-occurring species than about how interference impacts coexistence. In theory, intraspecific interference mechanisms, such as sexual conflict and territoriality, could promote coexistence by increasing intraspecific density-dependence relative to interspecific density-dependence. Conversely, interspecific interference could hinder local coexistence while promoting regional coexistence. Odonata is a promising taxon for advancing a general understanding of the role of interference in coexistence, in part because the types and intensity of interference vary within clades that exhibit minimal ecological differentiation. Ultimately, understanding how coexistence mechanisms structure Odonata communities will require investigating the roles of ecological differentiation and interference at both the larval and adult stages.