10.6084/m9.figshare.5756085.v1 R. I. M. Dunbar R. I. M. Dunbar Padraig Mac Carron Padraig Mac Carron Susanne Shultz Susanne Shultz ESM Dataset S1: Group Size Data from Primate social group sizes exhibit a regular scaling pattern with natural attractors The Royal Society 2018 optimal group size clustering social networks female cohort evolutionary rates 2018-01-04 11:57:13 Dataset https://rs.figshare.com/articles/dataset/ESM_Dataset_S1_Group_Size_Data_from_Primate_social_group_sizes_exhibit_a_regular_scaling_pattern_with_natural_attractors/5756085 Primate groups vary considerably in size across species. Nonetheless, the distribution of mean species group size has a regular scaling pattern with preferred sizes approximating 2.5, 5, 15, 30 and 50 individuals (although strepsirrhines lack the latter two), with a scaling ratio of approximately 2.5 similar to that observed in humans social networks. These clusters appear to form distinct social grades that are associated with rapid evolutionary change, presumably in response to intense environmental selection pressures. These findings may have wider implications for other highly social mammal taxa.