Phylogeny of Animalia
Phylogeny of the Animalia

Relationships among fifteen major phyla are shown. Significant evolutionary events include (1) differentiation of distinct tissue types in Eumetazoa, (2) development of bilateral symmtery in Bilateria, (3) development of body cavities in coelomates, and (4) evolution of deuterostomic development in Echinodermata and Chordata.

Figure ©1999 Campbell et al.;  text © 2005 by Steven M. Carr