Contents [hide]
1 Overview of affinities
1.1 Origin of name
2 Definition
3 Subdivisions
3.1 Craniata (Vertebrata)
3.2 Tunicata (tunicates, or urochordates)
3.3 Cephalochordata: Lancelets
4 Origins
5 Classification
5.1 Taxonomy
5.2 Phylogeny
6 Closest nonchordate relatives
6.1 Hemichordates
6.2 Echinoderms
7 See also
8 References
9 External links