Other common features include a single [[brain]] and a zig-zag [[muscle]] structure in the [[torso]], although these are not unique to the chordates.
Scientists believe that the chordata are closest to the [[arthropoda]] (shelled, joint-legged animals such as [[insect]]s and [[crustacean]]s), [[echinodermata]] (spiny-skinned animals such as [[starfish]] and [[sea urchin]]s), and [[annelida]] (earthworms) in biology, due to common features such as [[segment]]ation, which are not seen in other phyla such as the [[mollusca]] (molluscs) or [[coelenterata]] ([[jellyfish]] and [[sea anemone]]s). This is, of course, wrong because it promotes the "theory" of [[evolution]].
==See also==