Natural selection for costly nutrient recycling in simulated microbial metacommunities

► We study the stability of costly nutrient recycling in microbial metacommunities. ► We use an individual-based model of three microbial species in a spatial environment. ► Cross-feeding interactions lead to recycling, but participation can be costly. ► Patch-level selection for increased productivity promotes recycling. ► Recycling is locally unstable, but globally stabilised by multilevel selection.