Ongoing convergent evolution of a selfing syndrome threatens plant-pollinator interactions
Résumé
Plant-pollinator interactions has evolved early in angiosperm species radiation and is considered as a major trophic link in terrestrial ecosystems. Recent environmental changes however have led to pollinator decline that are susceptible to cause a disruption of plant-pollinator interactions. We used the resurrection ecology methodology to assay ancestral and contemporary descendant phenotypes in natural populations. We assessed patterns of mating system evolution in Viola arvensis, over the last three decades in the Parisian regional basin (France), a depauperate pollinator environment. Population genetic analyses revealed about 15% increase in realized selfing rates in the field during the last three decades. Using a two-generation common garden experiment, we documented trait evolution towards small and inconspicuous corollas, reduced nectar production and reduced attractiveness. Trait shifts were found to be convergent over the four studied populations. Our study demonstrates that plant mating system can evolve rapidly in natural populations in the face of recent environmental changes. Such rapid evolution towards a selfing syndrome illustrates the ongoing disruption of a major trophic interaction of natural ecosystems.
Domaines
Sciences du Vivant [q-bio]
Origine : Fichiers produits par l'(les) auteur(s)