A general model of local competition for space

Local competition for space across a wide array of taxa typically involves three mechanisms that we denote here as expansion (spreading into unoccupied habitat), lottery (replacing dead competitors), and overgrowth (encroaching on competitors along zones of contact). By formulating and analysing a simple, general model incorporating these features, we identify ecological conditions and life-history features that lead to stable coexistence or competitive exclusion (with or without initial-condition dependence) and gain insight by linking these to case studies in the literature. We demonstrate the importance of contact inhibition, a little-studied feature of overgrowth, and we show how life-history tradeoffs may influence and be influenced by local competition for space. The general model we present can help indicate whether local interactions are sufficient to explain patterns of coexistence or exclusion and can serve as the foundation for more specific, realistic models of spatial competition.