Mouillot and co-workers have investigated the correlation between ecosystem functions and rare species. Coral reef fish, alpine plants and tropical trees were studied. It has been suggested that generalist species can take over ecosystem function from specialist if these were to die out locally. In contrast, the authors find that vulnerable functions in ecosystems are "taken care of" predominantly by rare species, which means that is important to conserve such species for ecosystem resilience. Read the whole article in PLoS Biology.