Pollinator-mediated assemblage processes in California wildflowers

Community assembly is the result of multiple ecological and evolutionary forces that influence species coexistence. For flowering plants, pollinators are often essential for plant reproduction and establishment, and pollinator-mediated interactions may influence plant community composition. Here, we use null models and community phylogenetic analyses of co-occurrence patterns to determine the role of pollinator-mediated processes in structuring plant communities dominated by congeners. We surveyed three species-rich genera (Limnanthes, Mimulus, and Clarkia) with centers of diversity in the Sierra Nevada of California. Each genus contains species that co-flower and share pollinators, and each has a robust phylogeny. Within each genus, we surveyed 44-48 communities at 3 spatial scales, measured floral and vegetative traits, and tested for segregation or aggregation of: 1) species, 2) floral traits (which are likely to be influenced by pollinators), and 3) vegetative traits (which are like...