title: The evolution of signal-reward correlations in bee- and hummingbird-pollinated species of Salvia.
abstract: Within-individual variation in floral advertising and reward traits is a feature experienced by pollinators that visit different flowers of the same plant. Pollinators can use advertising traits to gather information about the quality and amount of rewards, leading to the evolution of signal-reward correlations. As long as plants differ in the reliability of their signals and pollinators base their foraging decisions on this information, natural selection should act on within-individual correlations between signals and rewards. Because birds and bees differ in their cognitive capabilities, and use different floral traits as signals, we tested the occurrence of adaptive divergence of the within-individual signal-reward correlations among Salvia species that are pollinated either by bees or by hummingbirds. They are expected to use different floral advertising traits: frontal traits in the case of bees and side traits in the case of hummingbirds. We confirmed this expectation as bee- and hummingbird-pollinated species differed in which specific traits are predominantly associated with nectar reward at the within-individual level. Our findings highlight the adaptive value of within-individual variation and covariation patterns, commonly disregarded as 'environmental noise', and are consistent with the hypothesis that pollinator-mediated selection affects the correlation pattern among floral traits.
authors.affiliation: Instituto Multidisciplinario de Biología Vegetal (IMBIV), Universidad Nacional de Córdoba - CONICET. CC 495, , CP X5000ZAA Córdoba, Argentina, Instituto de Ecología, Universidad Nacional Autónoma de México, , Apartado Postal 70-275, México Distrito Federal 04510, Mexico.
authors.forename: Santiago
authors.initials: S
authors.lastname: Benitez-Vieyra
authors.forename: Juan
authors.initials: J
authors.lastname: Fornoni
authors.forename: Jessica
authors.initials: J
authors.lastname: Pérez-Alquicira
authors.forename: Karina
authors.initials: K
authors.lastname: Boege
authors.forename: César A
authors.initials: CA
authors.lastname: Domínguez
mesh_terms: D000818:Animals; D001483:Base Sequence; D001516:Bees / Q000502:physiology; D001522:Behavior, Animal; D005075:Biological Evolution; D001717:Birds / Q000502:physiology; D035264:Flowers / Q000033:anatomy & histology* / Q000235:genetics*; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010641:Phenotype; D057048:Plant Nectar / Q000737:chemistry*; D054817:Pollination / Q000235:genetics*; D012201:Reward; D027544:Salvia / Q000033:anatomy & histology* / Q000235:genetics*; D012641:Selection, Genetic
chemical_list: D057048:Plant Nectar
keywords: floral signals; phylogenetic comparative methods; within-individual variation