Asymmetric migration decreases stability but increases resilience in a heterogeneous metacommunity

Abstract

Many natural communities are spatially distributed, forming a network of subcommunities linked by migration. Migration patterns are often asymmetric and heterogeneous, with important consequences on the ecology and evolution of the species. Here we investigated experimentally how asymmetric migration and heterogeneous structure affect a simple metacommunity of budding yeast, formed by one strain that produces a public good and a non-producer strain that benefits from it. We find that asymmetric migration increases the fraction of producers in all subpopulations of the metacommunity. Furthermore, asymmetric migration decreases the metacommunitys tolerance to challenging environments, but increases its resilience to transient perturbations. This apparent paradox occurs because tolerance to a constant challenge depends on the weakest subpopulations of the network, while resilience to a transient perturbation depends on the strongest ones.\n\nOne Sentence SummaryAsymmetric migration decreases the stability of experimental yeast metacommunities but increases their resilience to transient shocks.