Posterior probability of site classes for amino acids in two host response modifier genes . Shown for each site is the posterior probability of falling into the purifying (white), neutral (grey), or diversifying (black) class. Posterior probabilities were determined by Bayes empirical Bayes analysis. Dashed line at 0.5 shows the threshold for a site to be classified as diversifying. A) IL-18 binding protein. B) mitochondrial associated apoptosis inhibitor. Only the conserved C-terminal domain is shown, and the locations of the BH domains are indicated below the axis.