Known for their unique physical appearances, the starfish is one of the electrifying inhabitants of the underwater world. They are also known as sea stars. Though they are inhabitants of the ocean, they are not exactly fish. Apart from their unique physical structures, what distinguishes them from normal fish is that starfish do not have backbones, which means they are invertebrates. Because of their hard surfaces, predators like otters, birds and other fish do not trace the starfish as their food sources.
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| Komodo National Park starfish (Photo credit: Wikipedia) |
According to marine biologists, there are over 2,000 species of starfish. Starfish are generally found in different types of marine habitants like coral reefs, rocky shores, sea grass and kelp beds. Some of them are even found thousands of feet below the sand.
While describing their physical appearances, the size of Starfish ranges between one to ten inches each. However, the smallest Starfish can be less than one-half of an inch and the largest can be more than three feet in size. Depending on the species, the lifespan of starfish may vary from two to 35 years. You can see starfish in various colors including red, brown, pink and orange.
Starfish may have five or more arms which appear emerging out of their body. However, the number of arms can get to be 50 in many cases. The bottom surfaces of their arm are covered by suckers which act like pinchers. With the help of tube-like organs, starfish can gradually creep across the ocean floor. They can expand them by pumping sea water into the tubes.
Like any other living species, Starfish do not have normal eyes. Instead, they have eyespots that may be found on their bodies. Using these eyespots, they can trace foods and sense the lights and shapes in an area. Their eyespots are located at the tip of each arm. Their food-tracing habits keep them grazing along the sea floor. Starfish are carnivores and they enjoy eating snails, oysters, clams, mollusks and more. You can also find some species that eat algae.
Like their unique physical structures, starfish are also known for their unique ways of consuming food. Their mouth is in the base of their body and they have throats that are extended to the stomach. While taking a grasp on its prey, a sea star can extend its stomach through its mouth. It can digest the food outside the body through special enzymes and then the digested food gradually gets into the stomach through the throat. Every tiny organism that is eaten will be swallowed whole.
While talking about their lifestyles, they generally prefer to keep a distance from other species. This makes them solitary creatures. However, you may find them in groups on occasion.
An interesting fact about their arms is that starfish are capable of reviving their lost arms. When they are threatened by predators, they leave their arms behind and form new ones. This is a special type of defense mechanism applied by this unique living creature. However, it may take a year for such a being to grow its arm back to a full length.
Carlos J Garcia has written various supporting companion page articles for A Reading Place and if you would like to see the companion page to this one, please visit All About Starfish to see two related videos, a collection of photographs and more articles. If you would like to see a wonderful children's book, About Starfish on Amazon is a great choice. Article Source: EzineArticles |
