A comparison of the simultaneous analysis tree derived from nuclear and mitochondrial genes to the single-locus cladogram of LeDuc et al. . A). Strict consensus of 4 equally parsimonious trees (length = 1328, CI = 0.55, RI = 0.80) derived from the simultaneous analysis of Actin, RAG2, cytochrome b, and control region data. This tree is congruent with the results of the Bayesian analysis, except those nodes in the boxed insert (bottom left). Numbers to the left of each node are bootstrap proportions, decay indices, and posterior probabilities, respectively. Boxes mark nodes that have either improved resolution or are newly resolved in the simultaneous analysis; numbers in parentheses measure the change (increase, '+'; decrease, '-') in support indices. A circle denotes the Lissodelphininae clade. B). The cytochrome b cladogram of LeDuc et al. . Node numbers match those of the simultaneous analysis tree. The asterisk '*' indicates an additional clade of species represented in the LeDuc et al.  study but absent in our data set.