Transition:transversion plots. Uncorrected transition and transversion pairwise distances plotted against total distance for each of four loci obtained from combined MP analysis, drawn to same scale. (a), ADH5; (b), FGB7; (c), GPD3-5; and (d), 16S rDNA, 12SrDNA, and tRNA Valine. Closed circles, transition substitutions; and open circles, transversion substitutions. Note accelerated rate of transition substitutions of mtDNA.