This project will investigate how interacting species that depend on each other for their own livelihood cause each other to evolve. A broad goal is to understand how such interactions influence the diversification of life on Earth. The researchers will study one of the most ecologically important, highly diverse systems for studying these interactions: figs, their wasp pollinators, and the associated group of parasitic wasps that feed on figs but that don't pollinate them. They plan to test the novel hypothesis that some wasps are able to move onto new hosts, and that these host shifts ultimately lead to decreased genetic differences among wasp species, and thus a breakdown of species' barriers. The project will have important implications for agriculture and food production because the same processes at work in this fig-fig wasp system also determine crop-pest and crop-pollinator relationships. Many college students and young scientists will receive scientific training. A unique educational aspect of the project is the International Field Trip in Biology course, which will allow 12 undergraduates per year to conduct international field research in Panama.
The research approach is multidisciplinary, involving phylogenetics, population genetics, and volatile chemistry. Genomic sequencing will be used to: 1) obtain well-resolved evolutionary trees of genetic relatedness among Central American fig and fig wasp species, 2) identify subsets of fig species that are, unexpectedly, interbreeding (hybridizing) with each other, and 3) link hybridization of figs to changes in the floral "perfumes" used to attract pollinators, and which are also exploited by parasites to locate host plants. Because this project will include numerous fig and fig wasp species, it will provide the broad frame of reference needed to gain an in depth understanding of the biological and chemical mechanisms underlying the pattern and process of co-diversification across interacting fig and wasp lineages.