radial symmetry
Echinoderms are marine organisms that make up the phylum Echinodermata. They can be found in the ocean from the equator to the poles. There are roughly 6000 living species of echinoderms. They are among the most distinctive organisms within the animal kingdom. Members of the phylum include sea stars starfish , sand dollars, and feather stars, shown in Figure below . See Different But Equal at http://www. pbs. org/kcet/shapeoflife/episodes/ultimate. html for an introduction to echinoderms.