A comparative study of body size and clutch size across the parasitoid Hymenoptera

  • Traynor R
  • Mayhew P
  • 8

    Readers

    Mendeley users who have this article in their library.
  • N/A

    Citations

    Citations of this article.

Abstract

Across animal species, body size and clutch size often form part of a suite of associated life history traits, exemplified by the ‘‘fast-slow continuum’’ in mammals. Across the parasitoid Hymenoptera however, a major axis of life history variation is the development mode of the larva (koinobiosis versus idiobiosis), and body size and clutch size do not seem to form clear associations with this major axis. Here we use a large comparative data set and the latest phylogenetic information to explore hypotheses that might explain the variation in body size and clutch size across species in parasitoids. We find evidence for three novel evolutionary correlations: changes in the stage of host attacked by the parasitoid (i.e. egg, larva, pupa) significantly predict changes in both body size and clutch size, whilst in gregarious species changes to higher latitudes are associated with reduced clutch size.We also find a number of hypothesized cross-species (phenotypic) associations that, however, we cannot demonstrate are the result of evolutionary correlations: large bodied species in our data tend to lay small clutches; koinobionts are larger than idiobionts attacking the same host stage; tropical species are smaller than temperate species (Bergmann's rule). Our results provide support for theoretical models of trait evolution in parasitoids, whilst the associations between latitude and life history may help explain why species richness in the family Ichneumonidae peaks at intermediate latitudes. Our results also show the continuing value of phylogenetically-based comparative analyses and demonstrate that recent work on parasitoid phylogenetics has produced significant benefits for our understanding of life history evolution.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Authors

  • R.E. Ruth E Traynor

  • Peter J P.J. Mayhew

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free