One fundamental question that remains answered in ecology is: what is the relative contribution of biodiversity at different levels of organization to ecosystem functioning? In the context of frugivory and seed dispersal, this question could be approached from the perspective of one major seed disperser group, Neotropical bats, and how its members select the fruits they eat. The diversity of their interactions is key to understand processes of seed dispersal, natural succession, and forest restoration. To help fulfill this gap, my collaborators and I have been combining different approaches in studies that vary from field experiments to radio-tracking and network modeling. In this talk, I will summarize some of our findings, as well as our inferences about the consequences of fruit selection by bats from the individual to the community.
2. Results/Conclusions
The analysis of a comprehensive dataset of bat-plant interactions in the Neotropics corroborated the long-standing hypothesis that frugivorous bats of different genera feed more frequently on fruits of different genera. A series of cafeteria trials carried out in Brazil and Panama confirmed that those associations reflect preferences, as the supposedly preferred fruits remained the most consumed even in much lower abundance than other fruits. Also, bat species of the same genus, although preferring fruits of the same genus, focus on different species. One last cafeteria trial pointed out to evidence of individual specialization among frugivorous bats of the same population. From the plants’ perspective, two field experiments showed that, within the same plant species, larger fruits have a higher probability of being selected than smaller fruits. First, inter-individual differences in diet among bats affect the foraging patterns of the whole population and how those bats disperse seeds in heterogeneous landscapes. Second, fruit selection patterns influence the subgroup structure of local bat-fruit networks. Third, dietary specialization, geographic distribution, and phylogeny affect the guilds and the hierarchy of importance among different species in bat-fruit networks on a biogeographic scale. In summary, this series of studies showed that the decisions made by one individual bat have upscaling consequences that are reflected even in complex interaction patterns in the whole Neotropics.