Oviposition substrate affects adult mortality, independent of reproduction, in the seed beetle Callosobruchus maculatus

Abstract. Seed beetles (Coleoptera: Bruchidae) are commonly used to study the influence of reproduction on life‐span and senescence. To study the physiological trade‐off between reproduction and mortality, many experiments rely on manipulating access to oviposition substrates to manipulate the reproductive rate of females. The presence of host seeds, independent of reproduction, results in increased mortality of female Cullosobruchus muculutus. This influence on mortality varies between two host seed species, suggesting a role of either allelochemicals or energetic costs associated with behaviour on hosts. The influence of host seeds on survivorship, independent of reproduction, confounds the interpretation of cost‐of‐reproduction studies with seed beetles. This complication must thus be considered in the design and interpretation of life‐history studies of seed beetles and other insects.