  Contemporary Niche Theory is a useful framework for understanding how
organisms interact with each other and with their shared environment. Its
graphical representation, popularized by Tilman's Resource Ratio Hypothesis,
facilitates the analysis of the equilibrium structure of complex dynamical
models including species coexistence. This theory has been applied primarily to
resource competition since its early beginnings. Here, we integrate mutualism
into niche theory by expanding Tilman's graphical representation to the
analysis of consumer-resource dynamics of plant-pollinator networks. We
graphically explain the qualitative phenomena previously found by numerical
simulations, including the effects on community dynamics of nestedness,
adaptive foraging, and pollinator invasions. Our graphical approach promotes
the unification of niche and network theories, and deepens the synthesis of
different types of interactions within a consumer-resource framework.
