Evening primroses represent the most diverse group of hawkmoth-pollinated plants in North America. While many of these species converge in floral morphology, many diverge in floral scent. Geographic and phylogenetic variation in herbivore selection may be responsible for the diversification of floral scent in evening primroses, especially if the same traits mediate interactions with both herbivores and pollinators. In 2014 and 2015, we collected data on floral scent, floral morphology and herbivory across the geographic range of 14 species in the tribe Onagreae.
Results/Conclusions
Preliminary analyses suggest that intraspecific variation in floral scent is pervasive and correlated with the presence of a specialist herbivore, Mompha, in at least two species. Across the phylogeny, floral morphology and scent are associated with the presence of two herbivores, Mompha and Hyles lineata. Herbivore-mediated selection on floral traits has consequences for plant-pollinator interactions and can influence diversification at population, species and higher levels.