Comparison of host and parasite chronograms. The parasite chronogram is redrawn from Figure 3 and the host chronogram (with dates of major mammalian divergences) is redrawn from Bininda-Emonds et al. . Lines drawn between taxa indicate host-parasite associations. On the host chronogram, lineages with red and yellow boxes are parasitized by sucking lice and chewing lice, respectively. Mammalian lineages without shaded boxes are not known to be parasitized by any louse group. The Cretaceous-Paleogene (K-Pg) boundary indicated at 65 Ma by the dark gray vertical bar.