Convergent evolution of antlions and wormlions: similarities and differences in the behavioural ecology of unrelated trap-building predators

Antlions and wormlions are unrelated insect taxa, but both construct pit traps in loose soil and hunt similar prey. Owing to the likeness of their hunting strategies, and since no other animals construct similar traps, they demonstrate an intriguing case study of convergent evolution. We reviewed the literature of the last 16 years and compared the existing knowledge on trap-building antlions and wormlions. Whereas the knowledge on antlions has been accumulating, studies on wormlions are lacking, in particular studies on how wormlions sense prey and their cognitive abilities. Shared characteristics of the taxa include responses to increasing conspecific density, such as populating suboptimal microhabitats and altering their spatial pattern. The taxa differ, however, in other aspects, such as response to disturbance, prey size range, diversity in habitat selection and behavioural plasticity. We provide recommendations for future research on several levels of biological organization. If such research is conducted on co-occurring antlions and wormlions, the findings will contribute to a greater understanding of this convergent evolution, the extent to which it exists, and its limitations. This in turn will contribute to understanding how natural selection in specific environments has shaped similar phenotypes and which constraints limit the phenotypic outcome.