Ontogeny can provide insight into the roles of natural and sexual selection in cricket cuticular hydrocarbon evolution

The often complex cocktails of hydrocarbon compounds found on the cuticles of insects can serve both naturally and sexually selected functions, contributing to an individual’s ability to withstand water loss and attract mating partners. However, whether natural and sexual selection act synergistically or antagonistically on a species’  cuticular hydrocarbon (CHC) profile remains unclear. Here we examined the ontogeny of the CHC profile in a species of cricket Teleogryllus oceanicus while manipulating humidity during development. We predicted that juvenile crickets should produce only those compounds that contribute to desiccation resistance, while those compounds contributing specifically to male attractiveness should be produced only at sexual maturity. Further, if attractive CHCs come at a cost to desiccation resistance as predicted by some models of sexual selection, then males reared under low humidity should be constrained to invest less in attractive CHCs. Crickets reared under lo...