The feasibility principle in community ecology

The structure and function of ecological communities are conceptualized as an emergent outcome derived from their corresponding set of interacting populations embedded in a given environmental context. However, it has remained unclear whether common principles can explain the biodiversity patterns that we observe across different contexts. Notably, finding general principles can successfully guide conservation and restoration efforts to minimize negative anthropogenic effects on biodiversity. To address this gap, I propose the \emph{feasibility principle} in community ecology. Based on a compendium of theoretical work and empirical evidence on the feasibility of ecological communities, the proposed principle is based on three main postulates: (i) Ecological communities are feasible for a set of environmental contexts constrained by their internal structure. (ii) Self-organization leads to observable communities that are feasible for the largest set of local environmental contexts. (iii) Community transitions follow the path of least feasible changes within the environmental space. I summarize how the feasibility principle can be studied under a quantitative framework and contrasted with empirical data across a wide diversity of organisms and contexts. In the face of rapid climate change and habitat modification, I discuss how the feasibility principle can be used to assess the challenges and opportunities to mitigate biodiversity loss.