Bayesian consensus phylogram for SPF protein diversification
. Precursor numbers are cross-referenced in Additional files 2 and 3. Squares on the branches indicate Bayesian posterior probabilities (BPP) equal to or higher than 0.95 in combination with ML bootstrap support equal to or higher than 70. Circles indicate support for BPP alone. The support for four clades of N. viridescens precursor sequences (clades 1 to 4) is indicated in red. Nodes 1 to 3 indicate gene duplications that mark the divergence of these SPF clades. Node 4 represents the speciation event Salamandridae-Plethodontidae, and node 5 shows the onset of newt diversification. Blue dots show SPF protein sequences that have been identified as courtship pheromones [5,7].