Signatures of kin selection in a natural population of the bacteria <i>Bacillus subtilis</i>

Abstract Laboratory experiments have suggested that bacteria perform a range of cooperative behaviors, which are favored because they directed toward relatives (kin selection). However, there is lack evidence for cooperation and kin selection in natural bacterial populations. Molecular population genetics offers promising method to study populations the theory predicts will lead relaxed selection, result increased polymorphism divergence at genes. Examining Bacillus subtilis, we found consistent putatively traits higher greater than private expressed same rate. In addition, were able eliminate alternative explanations these patterns more deleterious mutations genes controlling traits. Overall, our results suggest by with an average relatedness r = .79 between interacting individuals.