Fig. 2. Divergence analyses for 1089 anaerobic genomes using 131 universal trees reveal clostridial species are closer to the root.

Analysis of 131 rooted trees of genes universally present in bacterial anaerobic taxa spanning major functional categories (sorted horizontally according to curated classifications shown on top; order as in Supplementary Data 3). Illustrative trees on the side portray the metric used in each analysis and identify the group at the root in each with yellow nodes. a Root-to-tip distance measured as node depth (normalized by the largest distance in each tree). b Root-to-tip distance measured as branch length (normalized by the largest distance in each tree).