Relationships among flowering plants and insects represent one of the great engines of terrestrial diversity. Plant scents are important drivers of these relationships (herbivory, plant defense, pollination), but remain poorly integrated into our understanding of floral evolution and pollination ecology. This study examines the role of floral scent in the diversification of the western North American evening primroses (Onagraceae) and their pollinators (hawkmoths, bees) and floral and seed predators (Mompha moths). Hypotheses that integrate across the genetic, phylogenetic, and functional dimensions of biodiversity are developed from the Geographic Mosaic Theory of Coevolution, which posits that variation in plant-animal interactions across the distribution of a species creates shifting evolutionary trajectories that drive local diversification. The research examines functional trait variation and selective forces in the field and experimental arrays, the genetic basis of the variation from the population to phylogenetic level using comparative genomics, and patterns of phylogenetic diversity in Onagraceae and Mompha. Mompha is a poorly understood genus that is the only known lepidopteran group to specialize on Onagraceae.
Few studies have tested the full spectrum of plant fitness outcomes when volatiles attract both mutualists and enemies, and no current studies have investigated scent-driven, geographic diversification in groups of interacting organisms. The hidden diversity of floral and seed predators and their potential as selective agents constitutes a considerable gap in pollinator-centric understanding of floral evolution. The integration of chemical ecology and comparative genomics provides a first attempt to explore the impact of past selective pressures on current patterns of diversity in non-model organisms. Additionally, the investigators will engage over 200 students (high school - graduate school, interns, and postdocs) in field work, experiments, and genomics/informatics activities. Private and public land owners and volunteers will participate in and/or be informed of conservation-focused components of this study.
