The Starfish, which are actually named Sea Stars, are not really fish despite the common name that has been given to them. Sea stars are echinoderms, found only in seas and often washed up on seashores.
The most striking characteristic feature of the starfish, or sea star, is the five pointed star shape of the most commonly seen variety. Sea stars actually come in a variety of types and many have far more arms than the usual five.
There are at least 2,000 species of sea stars living in all the oceans of the world. From the tropical habitats of The Caribbean to the icy sea floor of the Arctic, these unusual denizens of the oceans have a hard, bony, spiky skin that helps to protect them from most predators. They can be brightly colored to help camouflage themselves or to help scare off predators. There are no freshwater sea stars, and there are only a very few species that live in brackish water.
Sea Stars have the wonderful ability to regenerate limbs or sometimes even their entire bodies! By having all, or very nearly all, of their vital organs in their arms this helps these fantastic creatures to be able to regenerate their arm or a whole body. Some species of Sea Stars have to have the central body to regenerate while other species can grow a whole new sea star just from a severed limb.
If you have ever come across a Sea Star while you were strolling along the beach and turned it over, you probably noticed the tiny projections on the underside of the Sea Star. The little tube feet help the Sea Star to be able to move around and also to help open up a scallop or clam for a tasty meal.
The tube feet play a very important role for helping a Sea Star to obtain its food. Then the sea star pops out a stomach, stuffs the food inside, and then pulls that stomach back into the shell to pull the food inside.
Another really cool fact about the Sea Star is that it has two stomachs. The first stomach, known as the cardiac stomach helps the Sea Star to grab food outside its body. When the cardiac stomach comes back into the body, the food in it is transferred to the pyloric stomach which then is used to finish digesting it’s meal.
Ever wondered if a Sea Star has eyes? The sea star’s all have these microscopic eyes at the end of each of their arms. These tiny eyes enable the Sea Star to be able to see movement and also enables them to tell the difference between light and dark.
Sea Stars are also invertebrates, carnivores, can live up to 35 years, and they have no brains or blood! Sea Stars have a nervous system that is spread through out their arms and their “blood” is really just filtered seawater.
These are but a few facts about the Sea Star, also commonly known as the “star fish”. To find out more about this unusual sea creature check your local library, or the Web for more amazing facts about the Sea Star.