Figure 1.

Topologies for the deepest branches in the metazoan tree recovered in phylogenomic analyses. (a) Porifera (sponges) sister to all other metazoa. This hypothesis includes a clade designated Eumetazoa (E). (b) Ctenophora (comb jellies) sister to all other metazoa. (c) A sponge+ctenophore clade sister to all other animals. All trees shown include a clade named Parahoxozoa (P) [43]. The Parahoxozoa topology was fixed based on King and Rokas [10], but an alternative topology with bilateria sister to a placozoa+cnidaria clade is also plausible.