The evolution of parasitoid fecundity: a paradigm under scrutiny

An important assumption in insect parasitoid life-history theory is that, within parasitoid complexes (species assemblages associated with particular hosts), members attacking young host stages are more fecund than members targeting older ones. This hypothesis reflects the general trajectory of host survivorship curves: as a host cohort ages, availability to female parasitoids declines, as can the risk that the host and the parasitoid offspring it carries succumbs to extrinsic mortality. However, the analyses that provided empirical support for the hypothesis did not control for phylogeny. Using the original datasets, we use phylogenetically corrected analyses to test whether the results of the seminal study are upheld. Although we show those findings to be robust, the decline in fecundity could be a sampling artefact. We conclude that it would be unwise to assume the paradigm to be generally representative of natural parasitoid complexes.