Figure 1.

Phylogenies of mammals based on (a) molecular and (b) morphological datasets. The topology shown in (a) is modified from fig. 1 of Meredith et al. [4] and is based on an 11 000 amino acid alignment from 26 gene fragments, whereas that in (b) is modified from electronic supplementary material, figure S2A of O'Leary et al. [3] and is based on 4541 morphological characters (fossil taxa have been deleted). Branches are colour coded according to their membership of the superorders Afrotheria, Xenarthra, Laurasiatheria and Euarchontoglires. Node numbers in (a) correspond to the predicted ancestors for those nodes in figure 2.