Oil-collecting bee–flower interaction network: do bee size and anther type influence the use of pollen sources?

Pollination is an ecosystem service sustained by a differentiated use of resources among sympatric species. The bee size can influence the similarity in the use of resources, and poricidal anthers limit the access to pollen. Therefore, we evaluated the influence of body size and the anther type of pollen sources in Centridini–flower interaction network. We expected that the low niche overlap, promoted by these morphological parameters, would result in the formation of subgroups and lead to greater network resilience. We studied 15 bee species (n = 73 females) and identified their pollen sources. The bee size and anther type influenced the formation of subgroups in the community, and the larger bees used a higher proportion of flowers with poricidal anthers. Only the anther type influenced the robustness of the network. We conclude that the parameters analyzed influence both the use of resources by oil-collecting bees and their food niche breadth.