Phylogenetic relationships among major metazoan lineages. The topology of the tree is consistent with several recent molecular phylogenetic analyses [100-106]. Estimated divergence times for Cnidaria versus Bilateria, protostomes versus deuterostomes, and lophotrochozoans versus ecdysozoans are indicated in the white boxes . The origin of the homeobox gene superclass must have predated the split between animals, plants, and fungi.
Ryan et al. Genome Biology 2006 7:R64 doi:10.1186/gb-2006-7-7-r64