Basic Information on the Giant spined star -Pisaster giganteus
The Giant spined star can be from Vancouver Island, British Columbia to Isla Cedros, Baja California. Pisaster giganteus is a heavy sea star with a tough, firm body and thick arms. Its spines are large and long with swollen tips and are uniformly spaced. The body is light brown, tan or purple with blue rings surrounding the base of the spines. It has the ability to regenerate, if it loses all but one leg it still can grow the rest back in time. If it is cut in half those two halves can grow to be whole. They have many environment issues like change of temperature, change of wind conditions and tides all can effect their population. Their prey exhibit an avoidance when they are near the sea star.
The Nervous System of the Giant Spined Star-Pisaster giganteus
The Giant Spined Star nervous system is very simple like every starfish. It doesn't have a brain and not even a ganglia to coordinate movement. It does consist of a nerve plexus (a network of interlacing nerves), which lie below the skin. They have a nerve ring that surrounds the mouth, a radial nerve branches off from the ring and extends to each arm. The way they see is that they have eyespots on each arm that detect light. The eyespot contains light sensitive pigments that allow the star to detect shadows and changes of light. All the sensory information must go to the radial nerves, any memories must be stored in the radial nerves, and any decisions about what to do must be made in the radial nerves. And somehow, the five different radial nerves must coordinate those decisions if the starfish is going to get anywhere.