The Starfish
Starfish do not have brains, but they do have what people would call a "distributed brain". Starfish have a complex nervous system which has a network of interlacing nerves known as nerve plexus which lies within, as well as under the skin. The oesophagus, commonly known as the gullet, is also surrounded by a central ring which sends radial nerves into each of the arms. The ring nerves and radial nerves coordinate the starfish's balance and direction. Starfish do not have many sensory inputs but are sensitive to touch, light, temperature, and the status of the water around them. The tube feet which is a small hallow appendages, and spines are sensitive to touch, the eyespots are sensitive to light, and the tube feet are sensitive to chemicals and can be used to locate food.