Researchers at the Max Planck Institute for Evolutionary Biology in Plön, within the Department of Theoretical Biology, characterized a recently discovered dynamical regime of microbial communities and used it to explain empirical patterns of marine plankton. There, strong and diverse interactions, combined with weak dispersal, fuel a continuous turnover of the small set of very abundant species, such that success is ephemeral and every species is equivalent in alternating between rarity and dominance.