Understanding the structure (static pattern) and function (mechanistic dynamics) of biological communities, and the interplay between them, remains a central area of both basic and applied research in ecology. Progress is being made on the influences of predation and competition in shaping the structure and dynamics of ecological communities. In contrast, the integration of mutualism into food web studies has been exceptionally slow to occur. Here, I examine how traditional consumer-resource theory can be combined with recent network theory to more fully integrate mutualism into empirical and theoretical research on the structure and dynamics of communities.
First, I show how the consumer-resource interaction is inherent to nearly all pairwise mutualisms, as is the case for predation and competition. Using this consumer-resource mechanism of interspecific interaction, I then show how mutualisms can be integrated into traditional food webs using the senita food web module as a case study. Second, using bipartite mutualistic networks (which are essentially two trophic-level food webs of consumer-resource interactions), I show that structural properties can influence the dynamics of mutualistic communities, as is well recognized of more traditional food webs. Given the ubiquity of mutualisms in real food webs, it may well be that the complementary and synergistic features of mutualistic and predator–prey interactions collectively contribute to the stability of ecological communities as a whole.