Bayesian phylogenetic analyses of mismatch repair proteins. (a) Phylogeny of MutS homologs (MSH2-6) based on an alignment of 327 amino acids. Parameter means: α = 1.79, pI = 0.04 and lnL = -28040.35. (b) Phylogeny of MutL homologs (MLH1, 2, 3 and PMS1) from an alignment of 330 amino acids. Parameter means: α = 2.2, pI = 0.031 and lnL = -24034.03. For both (a) and (b), the tree shown is a consensus of 951 best trees. Blue and red taxa names indicate animals and fungi, respectively. Thickened branches refer to posterior probabilities from 0.95 to 1.0. Protein identifiers for D. pulex sequences (in bold) are in Additional File 2.