Deadly hunters hiding behind beautiful colors — meet the ocean's most successful star.
It's obvious why these creatures are called stars, but why they bear the name of fish is more of a mystery. They're not fish at all, but members of the tough-skinned group of marine invertebrates called Echinoderms. Starfish, or sea stars, may look like colorful toys or beautiful pieces of art to people, but to a clam, scallop, or oyster, starfish are deadly hunters. These peaceful-looking animals are some of the most abundant and successful predators in the ocean.
Imagine being a clam and having a headless monster wrap its multiple arms around you and then pull your shell apart with its hundreds of tiny suction-cup feet! Next, the starfish pushes its stomach out over your soft body and begins to digest you while you're still alive! If you're a mollusk, a hungry starfish like this is a dreadful sight indeed.
Echinoderms include not only starfish, but also sea urchins, sea lilies, sea cucumbers, and brittle stars. Most members of this family have defensive spines, and their bodies are arranged symmetrically around their mouths.
Brittle stars and basket stars are fragile members of the Echinoderm family that have unique styles of moving and feeding.
Starfish come in every color of the rainbow. Some are the most vividly hued of all marine invertebrates.
Scientists call the limbs of starfish arms, not legs. Starfish don't actually walk on their arms, but instead propel themselves on tiny appendages located on the arms' undersides. These appendages are called tube feet. So if you think about it, starfish have feet on their arms!
Feather stars—which are members of a group called Crinoids—are beautiful but grabby creatures. They only feed at night, extending and waving their arms to trap food particles. They look flexible, but these creatures are actually very brittle, and their arms break easily when they're attacked. Fortunately, they can just as easily regrow them. Crinoids lived in prehistoric seas at the time of the dinosaurs. In fact, the little round rocks that some native peoples used as beads are really fossils, pieces of ancient crinoids.
They're everywhere — Starfish are adaptable creatures that live at all depths in the oceans. Some species live along the shore, where they are regularly exposed to the air during low tides. Other species live on muddy or sandy sea floors. And even at the bottom of the deepest trenches, you'll find starfish that have adapted to a cold, lightless environment.
Source: Microsoft Oceans (1995) CD-ROM. Text liberated from original screen art; images, audio & clips restored from disc. Original media is Microsoft/supplier copyright — non-commercial educational preservation. Credits & Acknowledgements