Brittle star
Brittle stars are closely related to sea stars as they have similar anatomies with both of their mouths being in the center of their body and having similar uses for their arms/ legs. Lowe classifications for this species include Ophiurida, Phrynophiurida, and Oegophiurida. The nervous system is quite complex for this animal. it consists of a main nerve ring located around the central disk of the mouth. At the end of each arm, the nerve ring attaches to radial nerve’s (smaller nerves) which run to the end of arm limb. In addition to these nerves brittle stars have nerves located at the the base of their arms which allow them to sense chemicals and notice the presence or absence of light. Also they have tube feet which allow them to sense odors.