Do you know why the mouths of sea urchins are also referred to as Aristotle's lantern? It’s the name for their unique mouth structure, made up of five movable teeth used to scrape algae and food from rocks and reefs. The name comes from the philosopher Aristotle, who noticed an interesting resemblance between the sea urchin’s mouth and five sided horn lanterns of his day. The diadema urchin is located in Conservation Hall and is often seen climbing the front window. | New York Aquarium