Bimodal pollination systems in Andean Melastomataceae involving birds, bats and rodents

Floral adaptation to a single most effective functional pollinator group leads to specialized pollination syndromes. However, adaptations allowing for pollination by two functional groups (bimodal pollination systems) remain a conundrum rarely investigated. We tested if floral scent and nectar traits of species visited by two functional pollinator groups indicate specialization on either one of the two or (intermediate) bimodal systems. We studied pollination biology in four species of Meriania (Melastomataceae) in the Ecuadorian Andes. Pollinator observations and exclusion experiments showed that each species was effectively pollinated by two functional groups (hummingbirds/bats; hummingbirds/rodents; flowerpiercers/rodents), nectar composition followed known bird preferences and scent profiles gave mixed support for specialization on bats and rodents. Our results suggest that nectar rewarding Meriania species have evolved stable bimodal pollination strategies with parallel
adaptation...