The refractory period of female katydids (Orthoptera: Tettigoniidae): sexual conflict over the remating interval?

Female tettigoniids have a refractory period after mating during which they are sexually unreceptive. Because females obtain valuable nutrients as well as sperm at mating, there is likely to be sexual conflict over the duration of the refractory period; females should accrue male donations, whereas males should prevent their mates from accepting additional matings. We examined the effects of ampulla attachment duration and female diet on the induction of the refractory period of a zaprochiline tettigoniid. We find that, although the relationship between ampulla attachment duration and duration of the refractory period holds for females maintained on a high-pollen diet, poorly nourished females only show the typical onset of the refractory period when allowed to consume the spermatophylax. These results suggest that female interests may have a greater influence in determining the outcome of sexual conflict. Under some circumstances spermatophylax feeding may compensate for poor female nutrition leading to the typical refractory period. Sexual conflict over the remating interval could be instrumental in generating larger nutrient investments by male tettigoniids. [Behav Ecol 1991;2:276–282]