The sea potato is a large, heart-shaped sea urchin. It is sometimes referred to as a heart urchin. You often see pieces of its bare and very breakable skeleton on the beach. A live sea potato has lots of spines which are flattened across its body. Its spines are shorter than by sea urchins and look more like hair than spines. Actually, it looks a lot like a hairy potato. Sea potatoes live burrowed in the seabed and eat organic wastes. This makes them extremely sensitive to oil pollution on the sea floor.