Figure 1.

Phylogenetic relationship of three Bacillaceae (B1, B2, B3) clades, on which the evolutionary rates of gene families are estimated using DiscML. A, a constant rate is estimated on each phylogeny; B, separate rates are estimated for external branches ( μ ₁) versus internal branches ( μ ₂) on each phylogeny. These three clades were studied in our previous study on gene presence, absence, and fragments [20]. Gene families are recategorized, with gene absence and fragments as character state 0, single-copy genes as 1, and gene families with two or more members as 2.