Therefore, wars of attrition may occur in territorial odonates. In odonates, we found an abundance of evidence suggesting that contests involve physical attack and that the ability of sexual discrimination is sufficient. We investigated past research on the behaviour of odonates and butterflies aiming to clarify whether the two prerequisites of wars of attrition are fulfilled: (1) contestants can inflict substantial costs on nondisplaying opponents and (2) contestants can discriminate the sex of flying conspecifics. In addition, wars of attrition require flying insects to distinguish the sex of flying conspecifics because their aerial interactions begin when intruders fly into the territory. The implicit but important requirement in this model is that some forces that match the intensity of display of the two contestants are necessary, and failure to enforce matching allows foul contestants that delay or stop their display to avoid paying contest costs. The broadly accepted interpretation of their aerial interaction is a war of attrition, where two contestants perform costly displays, and the one that reaches its cost threshold earlier gives up. Males of various flying insects perform conspicuous aerial interactions around their mating stations. Based on our analyses, we make predictions about reproductive behavior for four species in which male mating displays are unknown. Likely due to a genetic correlation between sexes, female Opsiphanes and Caligo are more similar in wing morphology and body design to their congeneric males than to each other. In contrast, male and female Caligo generally showed similar wing morphology, which possibly results from the lower energy expenditure of perching behavior when compared with active flight. Opsiphanes males have higher wing aspect ratio and more distal centroid position than congeneric females, suggesting that the energetic demands of aerial displays led to sexual dimorphism in wing morphology. A comparison of five species of each genus suggests that male display behavior is associated with, and has likely influenced the evolution of their wing attributes and body design. While male Opsiphanes perform aerial displays, Caligo males perch and wait for receptive females. Males of Opsiphanes Doubleday and Caligo Hübner (Lepidoptera, Nymphalidae) species perform crepuscular displays along forest edges and in light gaps. There is noticeable variation in male mate-seeking behavior among species of Brassolini butterflies.