Assistant Professor University of South Carolina, South Carolina, United States
Abstract: In nature, local species interaction networks are dynamic, changing in composition and structural properties as new species disperse to the area, existing species become locally extirpated, and as existing links rewire to form new associations or dissolve old ones. These local-scale changes have important impacts on regional-scale metacommunity structure and stability, and understanding the role biotic interactions play in mediating these processes can yield important insights into the maintenance of interaction network structure across scales. In order to help bridge this gap, we present a theoretical model incorporating competitor-mediated dispersal (CMD) processes into a model of plant-pollinator network assembly across a spatially-explicit metacommunity. In addition to more broadly providing insight into feedbacks between biotic interactions and metacommunity dynamics within the context of mutualistic networks, we show how heterogeneities in patch quality and connectivity can enable the persistence of both generalist and specialist interactions that would otherwise competitively exclude each other in a single-patch system. We also show that the presence of CMD processes can also alter competitive outcomes across space, affecting the formation of “hotspots” or “coldspots” of specialization. Our study clearly demonstrates the importance of spatial processes for mutualistic network assembly, as well as their resultant effects on network dynamics and stability.
