Crab

Empty crab shells littering the beach are often mistaken for dead crabs.
As part of their growth process, crabs actually shed their old shells as they grow new ones.

Walking along the tide-line you may occasionally notice numerous crab shells on the beach. Many people mistake these empty shells for dead crabs. What most people do not know is that as crabs grow, they shed their shells and grow new ones in a process called molting. Discarded crab shells settle on the ocean floor until strong currents wash them ashore. Molted crab shells have all the external parts intact – including legs, antennae, eyes, and gill supports, which makes it difficult to tell whether or not you are looking at a dead crab or just a molt.