Speaker
Description
In recent years, great progress has been made towards understanding the properties of species-rich communities with random interactions by leveraging tools from disordered systems. In the simplest models, macroscopic simplicity comes at the expense of a lack of structure in the interaction matrix. We extend previous work to account for communities with structured weak interactions and explore different types of structure. We characterize a broad class of interaction matrices that give rise to the same phase diagram and equilibrium properties as the unstructured case. Finally, we describe a method to partition communities into a small set of clusters driving the dynamics of species. These clusters can be seen as grouping species having similar "ecosystemic" roles, and provide an intermediate level of coarse-graining in which species are still tracked individually but their dynamics are driven by only a few quantities with a simple ecological interpretation.
