Cuticular Hydrocarbons-Revealed Functional Groups and Seasonal Acclimation in Sympatric Fig Wasp Mating Assemblages

Interspecific mating can increase when sympatric species mature simultaneously, posing challenges for mate recognition and resource utilization. Cuticular hydrocarbons (CHCs) contribute to desiccation resistance and act as chemical signals in communication. However, it is not sufficiently understood how the CHC traits of sympatric species respond to overlapping ecological, reproductive, and seasonal pressures. This study examines variation in cuticular hydrocarbons among five Ficus semicordata-associated fig wasp species and explores potential links between CHC profiles, mate recognition, and seasonal environmental variation, complemented by male mate-choice assays in two species. Species-specific CHC profiles with sexual dimorphism, combined with male mate choice, are consistent with a potential chemical basis for mate recognition. Species that share resource acquisition strategies (functional groups) tend to exhibit similar CHC patterns. The CHC composition adjusted seasonally among the four dominant species, and these patterns varied among functional groups and between sexes. This indicates that even under shared host and comparable macroclimatic conditions, species and sexes maintain distinct chemical profiles through adjustments in the composition and proportions of CHC. These findings provide a foundational framework for predicting how chemical traits mediate ecological adaptation and speciation in coexisting insect communities under spatiotemporal pressures.