Predispersal seed herbivores, not pollinators, exert selection on floral traits via female fitness

Herbivores that oviposit in flowers of animal-pollinated plants depend on pollinators for seed production and are therefore expected to choose flowers that attract pollinators. This provides a mechanism by which seed herbivores and pollinators could impose conflicting selection on. oral traits. We measured phenotypic selection on. oral traits of Lobelia siphilitica (Lobeliaceae) via female fitness to determine the relative strength of selection by pollinators and a specialist predispersal seed herbivore. We were able to attribute selection on flowering phenology to the herbivores. However, no selection could be attributed to pollinators, resulting in no conflicting selection on. oral traits. Unlike pollinators, whose preference for certain. oral traits does not always translate into higher fitness, any discrimination by seed herbivores is likely to decrease fitness of the preferred. oral phenotype. Thus predispersal seed herbivores may be a significant agent of selection on. oral traits.