“…In the network formalism, species are represented by nodes, and interactions between species are described by links (reviewed by Pimm, 2002). The network approach is helping to describe community-level patterns of interspecific interactions and understanding how interactions coevolve in species-rich assemblages Guimara˜es et al, 2006;Jordano et al, 2003;Lewinsohn et al, 2006;Montoya et al, 2006;Prado and Lewinsohn, 2004). Our major challenge, however, is to infer what are the ecological and evolutionary factors that generate the observed community-level structure of ecological networks (Fig.…”