Fig choice by the pollinator of a gynodioecious fig: selection to rush, or intersexual mimicry?

Authors

  • J. C. Moore,

  • M. J. Hatcher,

  • A. M. Dunn,

  • S. G. Compton


J. C. Moore, M. J. Hatcher, A. M. Dunn and S. G. Compton, Ecology and Evolution Research Group, School of Biology, Univ. of Leeds, Leeds, U.K. LS2 9JT. – Present address for JCM: Dept of Genetics, Univ. of Pretoria, South Africa 0002 ( jcmoore@tuks.co.za ). Present address for MJH: School of Biological Sciences, Univ. of Bristol, Woodland Rd, Bristol, U.K. BS8 1UG.

Abstract

Due to selection to maximise the benefits accrued, conflicts of interest exist between mutualists. An extreme conflict occurs between gynodioecious fig trees and their pollinating wasps. Female wasps, which are required for pollination, cannot reproduce in female figs and should be selected to avoid them. We investigate fig choice in Liporrhopalum tentacularis, pollinator of Ficus montana. We show that entry rates are independent of fig sex and diameter, with wasps instead entering the first fig encountered (although significant between-tree differences in entry rates to figs were observed). This suggests that wasps are unable to discriminate between the sexes because of selection for inter-sexual fig mimicry. In conjuction with data on other species pairs, these findings imply that that the resolution of the conflict is ultimately under the tree's control, with the level of mimicry evolving in response to both the propensity of wasps to discriminate and the costs of them doing so.

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