Alignments were constructed using Muscle [40] with a maximum of 64 iterations. Multiple FastA was converted into PHYLIP format (for tree-building) with the EMBOSS program 'seqret' [41] . Trees were built with PhyML [42] using the GTR model BIONJ for the initial tree and optimized tree topology and branch lengths. Trees with fewer than 50 species used 16 rate categories and larger trees used 8. Transition/transversion ratio, proportion of invariant sites, and the shape parameter (alpha) of the gamma distribution were estimated. Tree processing (including rooting, computation of support values, and displaying) was done with the Newick Utilities [43] .