Unrooted phylogenetic tree of Bacteria. This tree was obtained after discarding all sites with evolutionary rate predicted to be above 2.2. Stars indicate branches with 100% bootstrap support (200 replicates). Bootstrap supports between 80% and 100% are shown, bootstraps below 80% have been removed for clarity. Aquificales are represented in bright red. Names of major groups are according to the NCBI taxonomy. Gracilicutes and Terrabacteria, two recently proposed superclades, are shown as dashed frames, and their names are between quotation marks to mark their unconsensual status.