The evolution of parasitoid fecundity: a paradigm under scrutiny


  • Mark A. Jervis,

    Corresponding author
    1. Cardiff School of Biosciences, Cardiff University, Biomedical Sciences Building, Museum Avenue, Cardiff CF10 3AX, UK
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  • Annika Moe,

    1. Department of Ecology, Evolution and Behavior, University of Minnesota, 1987 Upper Buford Circle, St. Paul, MN 55108, USA
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    • Present address: Department of Biology, Syracuse University, Syracuse, University Life Sciences Complex 114, 107 College Place, Syracuse, NY 13244, USA.

  • George E. Heimpel

    1. Department of Entomology, University of Minnesota, 1980 Folwell Avenue, St. Paul, MN55108, USA
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Ecology Letters (2012) 15: 357–364


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.