Mating experience induces females to avoid harmful males in the beetle Lasioderma serricorne

When there is sexual conflict over mating rates, males should develop persistence to increase their mating rate, whereas females are expected to evolve resistance to keep mating at a lower rate. In the beetle Lasioderma serricorne, female remating occurs as a result of male persistence, and there is conflict between the sexes over mating rates. However, there is little information on female resistance to the persistence of males. We found that female relocation behaviours were increased by mating experience, but this change in behaviour was not observed in males. Females were also more likely to relocate in the presence of males. To investigate whether the purpose of this change in behaviour is to enable females to avoid males, we assessed how female fitness components changed in relation to two treatments (easy and difficult avoidance). The female remating rate was lower when avoidance was easy, but no difference was observed in the mating rate. In the easy avoidance treatment, we found no difference in fecundity or longevity between females that rejected remating and those that mated only once, while life span was reduced by acceptance of remating. These results indicate that females that rejected remating successfully avoided the harm caused by males by increasing their relocation behaviour. In the difficult avoidance treatment, life span was reduced, irrespective of whether remating was accepted or rejected. In this situation, because they had less opportunity to avoid remating, females might have been more exposed to a second male and thus suffered from harmful persistence. Our results suggest that changes in behaviour after mating are a result of counteradaptation to male persistence because this prevents a decrease in female fitness (female life span) and an increase in male fitness (mating success) in L. serricorne.