This sea potato (Echinocardium cordatum) looks similar to its root vegetable namesake, but it's a sea urchin! The spines on this urchin are more hair-like than the spikes seen on some more commonly known urchins, and they lay flat across the urchin's body. They can be found buried in the sediments of the sea floor. In their burrow they separate themselves from the sand and mud with a layer of mucus, and they keep several holes in the sediment around them to breathe, eat and remove waste.