Fig. 3.

Phylogenomic subtrees a–d generated using maximum-likelihood methods and alignments of concatenated conserved proteins (54, 20, 206 and 315 proteins). The black colored branches designate aquatic groups, while the grey ones their closest relatives (found in soil/sediments). The circular symbols, situated at the tips of the branches, are proportional with genome size and depict gene densities (within genomes). The number of genomes present in the collapsed groups is specified in parenthesis. e Putative model of niche-directed genome evolution in freshwater Planctomycetes