What is a chordate?
In respect to other animals
- 3 germ layers (not a sponge)
- bilateral symmetry (not a cnidarian)
- tube gut (not a flatworm)
- deuterostome (not a mollusk, annelid, or arthropod)
- notochord (not an echinoderm)
A word about body cavity states in animal phylogeny
Unique features of chordates
- pharyngeal gill supports or pharyngeal arches
- dorsal hollow nerve cord
- notochord