CONICET | Buscador de Institutos y Recursos Humanos

When pollinators visit a sequence of flowers they experience a continuum of variation in advertisement traits and in the amount and quality of reward, ranging from full rewarding to deceptive flowers. They can combine this information, evaluate the reliability of plant signals and use previous knowledge to decide when to leave that plant. Hence, in most plant species the within-individual covariation among signals and rewards could be the target of pollinator-mediated selection if pollinators verify the reliability of floral signals and penalize cheating individuals. We examined whether within-individual signal-reward correlations evolve under selection at micro- and macroevolutionary levels, detecting the occurrence of current phenotypic selection on natural populations and testing the adaptive divergence of floral signals in plants visited by different pollinators. In the latter case, we used a sample of Neotropical Salvia species and took advantage of the differential use of floral signals by bees and hummingbirds to predict which specific traits are predominantly associated with nectar reward at the within-individual level. Our findings support the idea that signal honesty is selected by pollinators and highlight the adaptive value of within-individual variation.