Bayesian reconstruction of ancestral life history modes of plethodontid salamanders. Three ordered alternative life history states are considered: direct development (yellow), biphasic (dark grey), and paedomorphic (blue). Bayesian ancestral state reconstructions were performed in BayesTraits (see Methods). Pie diagrams at each node show the proportional probability (prob.) of each state, and the highest probability subtends each node. The phylogeny is based on Bayesian analysis of Rag1 sequences in BEAST. See also Additional file 4.