TY - JOUR T1 - Signatures of kin selection in a natural population of the bacteria <em>Bacillus subtilis</em> JF - bioRxiv DO - 10.1101/2022.11.07.515416 SP - 2022.11.07.515416 AU - Laurence J. Belcher AU - Anna E. Dewar AU - Chunhui Hao AU - Melanie Ghoul AU - Stuart A. West Y1 - 2022/01/01 UR - http://biorxiv.org/content/early/2022/11/08/2022.11.07.515416.abstract N2 - Laboratory experiments have suggested that bacteria perform a range of cooperative behaviours, which are favoured because they are directed towards relatives (kin selection). However, there is a lack of evidence for cooperation and kin selection in natural bacterial populations. Molecular population genetics offers a promising method to study natural populations, because theory predicts that kin selection will lead to relaxed selection, which will result in increased polymorphism and divergence at cooperative genes. Examining a natural population of Bacillus subtilis, we found consistent evidence that putatively cooperative traits have higher polymorphism and greater divergence than putatively private traits expressed at the same rate. In addition, we were able to eliminate alternative explanations for these patterns, and found more deleterious mutations in genes controlling putatively cooperative traits. Overall, our results suggest cooperation favoured by kin selection, with an average relatedness of r=0.77 between interacting individuals.Competing Interest StatementThe authors have declared no competing interest. ER -