Choice In Crickets Research Articles

Heritable variation in the timing of spermatophore removal, a mechanism of post‐copulatory female choice in crickets

Female crickets can exert post-copulatory mating preferences by prematurely removing a male's spermatophore after copulation, which terminates sperm transfer. Although most models of sexual selection assume that female mating preferences are heritable, there has been little work addressing genetic variation underlying post-copulatory mate choice. We used a paternal half-sib design, in which different males were randomly assigned as mates to several females to create half-sib families, to determine the heritability of spermatophore retention time in female house crickets, Acheta domesticus. There was significant additive genetic variance in the timing of spermatophore removal by females [h(2) = 0.50 +/- 0.19 (+/- SE)], suggesting that the timing of spermatophore removal is determined, in part, by the female's own genotype independent of the quality of her mate. The relatively high heritability of spermatophore retention time may be reflective of the absence of strong selection on this trait, consistent with previous work showing no difference in the fitness of females permitted to freely remove the spermatophore of their mates and those forced to accept complete ejaculates.

No direct or indirect benefits to cryptic female choice in house crickets (Acheta domesticus)

Cryptic female choice in crickets occurs through the premature removal of a male’s spermatophore after copulation, which terminates sperm transfer. Although it is known that this behavior can directly influence the paternity of offspring, its effects on female fitness have not been directly assessed. We tested the hypothesis that spermatophore removal by female house crickets (Acheta domesticus) confers fitness benefits on females, by randomly assigning mates to females but permitting some females to freely remove spermatophores after mating (cryptic-choice treatment) while forcing others to accept complete ejaculates (nochoice treatment). Although there was about a two-fold difference in the volume of ejaculate received by females of the two treatments, there were no significant differences in female longevity, reproductive output, or offspring quality, as measured by offspring mass and developmental time. Although differential spermatophore removal by females imposes strong sexual selection on males, the absence of a clear treatment effect suggests that females obtain no direct or indirect genetic benefits through their postcopulatory mating preferences. Key words: Acheta domesticus, crickets, cryptic female choice, indirect genetic benefits, offspring fitness, spermatophore, sexual selection. [Behav Ecol]