Sun, Surf, and . . . Poo?

When you build a sandcastle at the beach, you may not know that some of your building material is actually fish poo! Parrotfish have some of the strongest teeth in the world. These tough teeth help them chow down on coral in the ocean. Then they excrete (poo) the hard stuff as sand.

One parrotfish can produce up to 1,000 pounds of sand a year.