Most flowering plants depend on pollinators to reproduce. Thus, evaluating the robustnessof plant-pollinator assemblages to species loss is a major concern. How species interactionpatterns are related to species sensitivity to partner loss may influence the robustness ofplant-pollinator assemblages. In plants, both reproductive dependence on pollinators(breeding system) and dispersal ability may modulate plant sensitivity to pollinator loss. Forinstance, species with strong dependence (e.g. dioecious species) and low dispersal (e.g.seeds dispersed by gravity) may be the most sensitive to pollinator loss. We compared theinteraction patterns of plants differing in dependence on pollinators and dispersal ability in ameta-dataset comprising 192 plant species from 13 plant-pollinator networks. In addition,network robustness was compared under different scenarios representing sequences ofplant extinctions associated with plant sensitivity to pollinator loss. Species with differentdependence on pollinators and dispersal ability showed similar levels of generalization.Although plants with low dispersal ability interacted with more generalized pollinators, low-dispersal plants with strong dependence on pollinators (i.e. the most sensitive to pollinatorloss) interacted with more particular sets of pollinators (i.e. shared a low proportion of polli-nators with other plants). Only two assemblages showed lower robustness under the sce-nario considering plant generalization, dependence on pollinators and dispersal ability thanunder the scenario where extinction sequences only depended on plant generalization (i.e.where higher generalization level was associated with lower probability of extinction). Over-all, our results support the idea that species generalization and network topology may begood predictors of assemblage robustness to species loss, independently of plant dispersalability and breeding system. In contrast, since ecological specialization among partnersmay increase the probability of disruption of interactions, the fact that the plants most sensi-tive to pollinator loss interacted with more particular pollinator assemblages suggest thatthe persistence of these plants and their pollinators might be highly compromised.
The robustness of plant-pollinator assemblages: Linking plant interaction patterns and sensitivity to pollinator loss
Year: 2015