Seasonal consistency of the assembling rules in a bird-fruiting plant network

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There is an ongoing debate on whether species' traits or neutrality generate recurrent patterns of mutualistic networks. Although there have been recent advances on the issue, many studies neglect the seasonal dynamics of these drivers. In this study, we investigated how pervasive are the drivers (i.e. species’ size, phenological overlap and species relative abundance) of the frequency of pairwise interactions and the aggregate metrics of seasonal seed dispersal networks in a semideciduous forest from the savannahs of Southeastern Brazil. We used a likelihood approach and built probability matrices based on different drivers to compare how they fit in the frequency and structure of the seasonal observed networks. We found that in both seasons trait-based processes, especially phenological overlap between species, best predicted the frequency of pairwise interactions. However, species relative abundances performed better than species traits in explaining most of aggregate network metrics in both seasons, except for the interaction evenness. These findings suggest that ecological and evolutionary processes are seasonally pervasive and determine the ability of species to interact with their partners. Besides, the general structure of the seasonal networks is less sensitive to species traits and its drivers remain seasonally constant. We conclude that our ability to understand the complexity of plant-frugivore interactions depends on assessing the contribution of species traits and their relative abundances to the structure of seasonal-detailed networks.