radula are made of a hard mineral called magnetite, which resists wear as it scrapes the rock. A few chiton species catch larger prey, such as small shrimp. They wait with the front part of their mantles raised until likely prey wanders underneath, then clamp down to trap it.
Chitons do not have eyes, but they do have organs on the surface of their bodies that allow them to detect light. This simple sense helps them to react quickly to shadows falling over them by clamping down tightly to the surface.
HABITATS AND BREEDING
Chitons are usually found on rocky, seabeds in tidal or in shallow water. Most chitons hide in crevices during the day, usually creeping out at night to feed. Not all chitons live in shallow water, and some are found at depths of 1,200 feet (400 m).
Most chitons are between 1 and 3 inches (2.5 to 7.5 cm) long, but some are much larger. Some chitons live for as long as 20 years, but many chitons fall victim to predators such as starfish and octopuses.
Chitons usually breed by shedding eggs or sperm into the sea. The fertilized eggs hatch into larvae (young form) that float in the plankton at first, then settle to the seabed to complete their development. Some chitons retain their larvae inside bodies, releasing them only when they are larger and more developed. Although this limits the number of eggs that can be produced, the young have a better chance of survival.