Nutrition during sexual maturation and at the time of mating affects mating behaviour in both sexes of a burying beetle

Theory predicts that the outcome of mating interactions should be influenced by the condition of both males and females. Firstly, females should base their mating decisions on reliable cues about male quality, which are often condition-dependent. Secondly, the costs and/or benefits of being choosy during mating may depend on the female’s own condition. Finally, when males divide their time between different mating tactics, investment to alternative mating tactics may depend on male condition. Here we examine the effects of male and female nutritional condition on mating behaviour in the burying beetle Nicrophorus vespilloides. We manipulated male and female nutritional condition either during sexual maturation or at the time of mating and monitored female mate choice and male mating tactics. We show that females in poor nutritional condition (i.e., starved either during sexual maturation or at the time of mating) prefer to mate with males in good nutritional condition over males that are starved at the time of mating. In contrast, well-fed females showed no such preference. Furthermore, males that were starved during sexual maturation increased their investment to alternative mating tactics by spending more time signalling for females. Our results add to evidence suggesting that females in poor condition bias mating towards males in good condition although it is currently unclear why females in poor condition are choosier in this species. Ours is the first study to demonstrate that nutritional condition during sexual maturation can influence mating behaviour, which may have implications for the rate and direction of sexual selection.