Spiteful Interactions in a Natural Population of the Bacterium Xenorhabdus bovienii

An individual behaves spitefully when it harms itself in the act of harming other individuals. One of the clearest potential examples of spite is the costly production and release of toxins called bacteriocins. Bacteriocins are toxins produced by bacteria that can kill closely related strains of the same species. Theoretical work has predicted that bacteriocin-mediated interactions could play an important role in maintaining local genetic and/or species diversity, but these interactions have not been studied at biologically relevant scales in nature. Here we studied toxin production and among-strain inhibitions in a natural population of Xenorhabdus bovienii. We found genetic differences and inhibitions between colonies that were collected only a few meters apart. These results suggest that spite exists in natural populations of bacteria.