The ecology and evolution of fig wasp communities

I use the fig/fig wasp system to address several questions in the fields of evolutionary and community ecology. I present a general review of speciation and community ecology in insects on plants in general and in fig trees (genus Ficus) and fig wasps (Hymenoptera: Cha1cidoidea) in particular. Following on from this introduction are four experimental chapters. The first experimental chapter investigates the contrasting impact of two genera of parasitic, or non-pollinating fig wasps, on their host Ficus and its pollinating wasps. I present my findings in terms of community ecology and mutualism stability. In the second experimental chapter I describe the community of fig wasps associated with two Ficus species from the Australasian Ficus section Ma/vanthera. Using behavioural, ecological and molecular barcoding data I investigate the host Ficus specificity and trophic role of each genus of wasp. Furthermore I carry out a detailed investigation into the mode of speciation in a key kelptoparasite genus: Sycoscapter (Pteromalidae: Sycoryctinae), highlighting the role of ecological speciation in generating diversity. In the next chapter I present a global multi-gene phylogeny of the subfamily Sycoryctinae before evaluating its age, origins and mode of radiation in relation to other major components of fig wasp communities. The final experimental chapter addresses the assembly of fig wasp communities over evolutionary time. I combine phylogenetic and ecological data from three wasp communities associated with three Ficus species from different continents to investigate the roles of niche stasis and niche lability in shaping community structure. I fmd that overall, general ecological rules appear little constrained by the local pool of insect species in these complex, globally dispersed and multi-trophic communities. A general discussion is presented in the fmal chapter in which I highlight areas for future research and provide closing comments. /.EThOS - Electronic Theses Online ServiceGBUnited Kingdo