Mating and social contact change egg production and longevity in adult females of the mirid Lygus hesperus

Abstract

There is frequently a tradeoff between fecundity and longevity, but the relationship is inconsistent across species and influenced by various exogenous and endogenous factors. Previous studies of Lygus hesperus Knight (Hemiptera: Miridae) established that egg production is promoted by insemination, at least temporarily, but little is known about the long‐term effects of mating and nonsexual interactions with conspecifics on egg production and female lifespan. To elucidate these relationships, survivorship and oviposition rate were tracked daily in females that were isolated or paired with a fertile male or another female throughout their adult lives. Mating rates were determined by postmortem examination. Results indicate that male‐specific stimuli accelerate female reproductive maturation, and that mating elevates oviposition rate. However, females paired with either a female or male companion had shortened lifespans, suggesting that social contacts exact a significant cost in this solitary species. Despite the negative impact of conspecific interactions and the finding that a singly mated female has sufficient sperm to fertilize a lifetime supply of eggs, many females were found to have mated more than once. Multiply mated females had higher sustained oviposition rates, lived longer, and had greater lifetime fecundities. Collectively, no strong evidence was found of a direct physiological link between fecundity and longevity, but environmental factors and mating were found to significantly influence both traits.