This proposal addresses the major questions of how offspring survivorship and competitive ability influence adult reproductive behavior in certain species of neotropical insects whose larvae develop in water-filled treeholes. Because these species use the same limiting resource (i.e. treeholes), and females are predictably found in light gaps, differences in mating systems cannot be fully explained in terms of the distribution of reproductive resources (the traditional paradigm). The discrete nature of the larval habitat allows assessment of success in terms of the relative number of offspring surviving to emergence. Although previous research in Panama suggests that predation among larvae render territorial defense ineffective for some species, experimental confirmation of this result is needed. If the working hypotheses are supported, this study will be one of the first to demonstrate a role of interspecific competition in the evolution of mating systems.
