Changes in the structure of seed dispersal networks when including interaction outcomes from both plant and animal perspectives

Interaction frequency is the most common currency in quantitative ecological networks, although interaction quality can also affect benefits provided by mutualisms. Here, we evaluate if interaction quality can modify network topology, species’ role and whether such changes affect community vulnerability to species loss. We use a well-examined study system (bird-lizard and fleshy-fruited plants in the ‘thermophilous’ woodland of the Canary Islands) to compare network and species-level metrics from a network based on fruit consumption rates (Interaction Frequency, IF), against networks reflecting functional outcomes: a Seed Dispersal Effectiveness network (SDE) quantifying recruitment, and a Fruit Resource Provisioning network (FRP), accounting for the nutrient supply of fruits. Nestedness decreased in the FRP and the SDE networks, due to the lack of association between fruit consumption rates and (1) nutrient content, and (2) recruitment at the seed deposition sites, respectively. The FR...