James Patrick O'Dwyer, University of Illinois, Department of Plant Biology

Abstract: Models of microbial interactions have been developed in recent years, drawing from taxonomic abundances via amplicon sequencing. Many of these models assume that dynamics through time are primarily driven by pairwise interactions between taxa, but with the drawback that how these interaction strengths may change with environmental context is less than clear. Here we model the consumption and exchange of resources explicitly, and show that these processes imply new results and principles for the stability of ecological communities. We go on to develop stochastic versions of these models, and demonstrate a transition between regimes that resemble neutral and niche-dominated dynamics and static patterns. Finally, I’ll show some recent work on more general stochastic models with individual variation, and their consequences for coexistence and stability.