Evolutionary history of a plant-frugivore metanetwork in a defaunated tropical forest

Abstract

Plant-frugivore interactions are essential for the maintenance of tropical forest, therefore a timely challenge on the conservation agenda. Habitat fragmentation and defaunation are among the main human-made disturbances affecting the persistence of these interactions. Such effects at the community level have been detected, among others, by the use of ecological networks and corresponding species topological roles. Put bluntly not only ecological time processes are affected but also evolutionary history is lost when species and interactions are vanished. Here we will combined ecological and spatial network analyses with the phylogenetic information of plant and bird species to ask whether the centrality of plant-frugivore interactions are related to their evolutionary history and to estimate how much of this evolutionary history has been lost with defaunation in a highly diverse tropical forest. We will use a dataset composed of 16 plant-frugivore communities from the Atlantic Forest, a highly diverse and threatened tropical forest. We will use linear regressions to test whether interactions with higher centrality (degree, betweenness and closeness) in the spatial network are the main landscape connectors, are more recent in the phylogenetic tree and show higher evolutionary distinctness. Furthermore, we will estimate a proxy of defaunation for each community according to the body mass of the expected and observed frugivores, and use General Least Square models to estimate how much of the evolutionary history of interactions is lost when the larger frugivores are vanished. (AU)