Echinodermata - Echinodermata are water organisms that live in only salt water, and are known for their 5 point body type. Their fossilized shell produces the majority of limestone in eco-systems. Echinodermata are able to regenerate body parts no matter what the circumstances are. The Echinodermata have a underdeveloped nervous system, which is a problem for them. Despite their motor skills and a few eye spots they lack the most common features of a nervous system. Most have a de-centralized nervous system, which helps them sustain major damage and still survive. Most Echinodermata such as starfish use a radial nerve that controls the whole body and is in charge of finding mates and food because they lack a brain. They also lack proper ears and eyes.
Starfish - Starfish have no brain. The central nervous system of a starfish consists of a radial nerve running the length of each ray and a circumoral nerve ring connects the radical nerves.
Sea Cucumber - The sea cucumber has no true brain. It has five major nerves that run from the nerve ring down the length of the body beneath each of the ambulacral areas.
Sea Urchin - The Sea Urchin has no brain like all the species in this phylum. The center is a large nerve ring encircling the mouth just inside the lantern.
Starfish - Starfish have no brain. The central nervous system of a starfish consists of a radial nerve running the length of each ray and a circumoral nerve ring connects the radical nerves.
Sea Cucumber - The sea cucumber has no true brain. It has five major nerves that run from the nerve ring down the length of the body beneath each of the ambulacral areas.
Sea Urchin - The Sea Urchin has no brain like all the species in this phylum. The center is a large nerve ring encircling the mouth just inside the lantern.