The phylum Echinoderamata contains what we may more commonly know as Echinoderms. Adults of these organisms are fairly easily recognisable by their (usually five-point) radial symmetry, and include starfish, sea urchins, sand dollars, and sea cucumbers. Adult echinoderms are found on the sea bed at every ocean depth, from the intertidal zone to the abyssal zone. The phylum contains about 7000 living species. At the top level, there are 3 living subphyla, then each one is divided into a number of classes, subclasses, orders, families etc., within. To present this with a level of simplicity, the 3 subphyla are represented by the tiles below. Click or touch a thumbnail text to explore a particular branch of these fascinating and diverse creatures.