Spermatophore retention may accommodate sexual signal loss in pacific field crickets
Kota, Mounica (2021), Spermatophore retention may accommodate sexual signal loss in pacific field crickets, Dryad, Dataset, https://doi.org/10.5061/dryad.pc866t1jr
Sexual signals are gained and lost over evolutionary time. While signal gain has obvious fitness benefits, signal loss should present significant costs due to decreased mating opportunities. Because sexual signal loss has rarely been observed in real time, it is unclear how this process unfolds in nature. Just as female mating preferences can promote evolutionary gain and elaboration of sexual signals, they may also facilitate signal loss. We investigated how two components of female mate choice are involved in rapid sexual signal loss in the Pacific field cricket (Teleogryllus oceanicus), in which many males have lost the ability to sing. Males that can sing (“normal-wings”) and obligately silent males (“flatwings”) coexist in Hawaiian populations. While we know that females prefer not to mate with flatwings, we tested whether females discriminate against flatwing males before copulation due to the lack of song, or something inherent about their wing morphology. We combined this assessment with a test of post-copulatory preference by presenting females with either a normal-wing or flatwing male in the presence or absence of a courtship song stimulus. Females took significantly longer to mount males in the absence of courtship song regardless of male wing morph. This is the first evidence that females discriminate against the absence of song during mate choice, not male wing morph. However, females retained spermatophores for equally long regardless of male wing morph and whether they heard courtship song. Pre- and post-copulatory sexual selection do not operate synchronously in this system, which may help explain the success of the silent morph in wild populations.
National Science Foundation, Award: IOS-1261575