Echinoderm

Echinoderm

=**__Phylogenetic Tree __**= =__Unique Facts __=
 * KALM, OLIVIA ||
 * LAUNSBACH, CHARLES ||
 * STAUDT, ERIC ||
 * NEWCOMB, BENJAMIN ||
 * ELLIOTT, SARAH ||
 * ISOPO, MARIO ||
 * SQUADERE, MICHAEL ||
 * MOROUKIAN III, RAFFI ||
 * All echinoderms have one thing in common: radial symmetry. This means that the creatures have appendages (or body construction) which point outward from the center of the body like the spokes on a bicycle wheel.
 * They have hundreds of tiny feet that are arranged in rows on each side of the star, which are called tube feet. (podia)
 * The animal has muscles in the tube feet which are used to retract them. By expanding and retracting the right tube feet in the proper order, the creature can walk
 * The sea star has a light sensitive organ at the tip of each ray, called an eyespot. When moving across the ocean floor, the sea star usually leads with one ray, probing the surface ahead. Although the star cannot see in the way we do, it can detect the presence and direction of light, and does seem to have some idea where it is headed.
 * Sea stars are capable of regenerating lost limbs in the even that one or more is severed or damaged. The wound first closes off, and over a certain amount of time, a new limb will begin to grow.
 * Echinoderms only live in water. And more specifically salt water. Echinoderms cannot survive in freshwater.
 * In a way, echinoderms can reproduce asexually and sexually. They can reproduce lost limbs on their own body, and can sexually reproduce with another of the same species.
 * Echinoderms are in the Phylum of marine animals.
 * Echinoderms can be found in great depths of the ocean. From the intertidal zone to the abyssal zone.
 * Many echinoderms can also form suckers on the ends of their tube feet. These suckers can be used to capture and hold prey, or to hold onto rocks in a swift tide or current.
 * __Classes of Animals Included in Echinoderm __**
 * ===Asteroidea (starfish or sea stars): Leptasterias hexactis, Star fish have slightly evolved senses of smell, touch, and taste. They are also able to react to the presences of light. For the most part they consume small prey whole for food, however they have to extrude their stomachs to consume larger prey outside their bodies. ===
 * ===Ophiuroidea (brittle stars): Ophiopholis aculeate, Brittle fish can be found in most oceans but mainly in the tropical oceans of the world. The species contains 2000 different types of brittle fish all varying in characteristics such as color. Brittle fish feed mainly on decaying matter and microscopic organisms at the muddy bottoms of the ocean. ===
 * ===<span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Echinoidea (sea urchins): sea urchins are able to move by using short to long, movable spines, which is a natural characteristic of a sea urchin. In between the sea urchins spines are small pincer-like organs called pedicellariae. This organ is used by the sea urchin in order to clean and defend itself. This organ also contains a powerful toxin. ===
 * ===<span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Crinoidea (feather stars): Florometra serratissima, feather stars will only swim if they are disturbed or startled. There are about 625 different species of feather stars and they can be found in a majority of oceans at any depth. At one point in history, feather stars were one of the most prominit organisms on earth. ===
 * ===<span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Holothuroidea (sea cucumbers): similar to star fish and sea urchins there are some 1,250 know species. Sea cucumbers feed on tiny particles like algae or waste materials. Small Sea Cucumber eggs can be prey to fish. ===
 * ===<span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Holothuroidea (sea cucumbers): similar to star fish and sea urchins there are some 1,250 know species. Sea cucumbers feed on tiny particles like algae or waste materials. Small Sea Cucumber eggs can be prey to fish. ===


 * __ Approximate Size of Species __**
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">There are approximately 13,000 species in fossil record of echinoderms.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Phylogenetic relationships, and in some cases, status as monophyletic groups, remain unclear for the extinct classes.

//Echniothrix calamaris// - banded sea urchin (//Wana//)
 * __ Some Species Include: __**
 * [[image:Slate_pencile_urchin.jpg]]
 * //Heterocentrotus mammillatus// - <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">slate pencil urchin

//Culcita novaguieae// <span style="font-family: Tahoma,Geneva,sans-serif; font-size: 120%;">- cushion sea star

//Ophiocoma// //spp//. - brittle stars

//Actinopyga mauritiana// - speckled sea cucumber


 * __<span style="color: #18cd18; font-family: Tahoma,Geneva,sans-serif; font-size: 170%; line-height: 27px;">Geographic Distribution __**
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Species of Echinoderms normally live in coral reefs
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Normally in the various holes and indents on rocks
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Some live in Shallow rocky waters on some shore lines.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Most of these Coral reefs are located in Hawaii, Australia, Brazil, Indonesia, Cuba, Arabia, Madagascar, the southern coast of Japan, and in the Indian and Pacific oceans.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">They only live in saltwater bodies because they cannot survive in freshwater.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">They can survive in almost all depths, latitudes, and environments in the ocean.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">The larvae of many echinoderms can swim great distances with aid from the ocean currents and are pelagic. this reinforces the global distribution of the phylum.

__**<span style="color: #d500ff; font-family: Georgia,serif; font-size: 170%; line-height: 27px;">Feeding Mechanisms **__
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Crinoids and some brittle stars tend to be passive filter-feeders, absorbing suspended particles from passing water; sea urchins are grazers, sea cucumbers deposit feeders, and seastars active hunters.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Many sea urchins graze on the surfaces of rocks, scraping off the thin layer of algae covering the surfaces. Other toothless breeds eat smaller organisms, which they catch with their tube feet.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Sea cucumbers may be suspension feeders, sucking vast quantities of sea water through their stomachs and absorbing anything that they can digest as food. Others use their feeding apparatus to actively capture food from the sea floor.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">The sea stars can use connective tissue to lock their arms in place and maintain a force on the prey while exerting minimal effort; the unfortunate victim must expend energy resisting the force with its adductor muscle. When the adductor tires, the sea star can insert its stomach through the opening and release gastric juices, digesting the prey alive.
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Many echinoderms can also form suckers on the ends of their tube feet. These suckers can be used to capture and hold prey.


 * __<span style="color: #ffb700; font-family: Arial,Helvetica,sans-serif; font-size: 200%; line-height: 27px;">Reproductive Mechanisms __**
 * Echinoderms become sexually mature after about 2-3 years, depending on the species or the environmental conditions
 * Fertilization takes place out in the open water because the eggs and sperm are released into the water.
 * Another strategy that has evolved in some sea stars and brittle stars is the ability to reproduce asexually by dividing in two halves while they are small juveniles, while turning to sexual reproduction when they have reached sexual maturity.
 * In some species of feather star, the embryos develop in special breeding bags, where the eggs are held until sperm released by a male happen to find them and fertilize the contents.
 * Some echinoderms carry their young between the pricks of their oral side, and heart urchins possess breeding chambers.
 * With brittle stars, special chambers can be developed near the stomach bags, in which the development of the young takes place.
 * Some seastar populations can entirely reproduce asexually purely by the shedding of arms for long periods of time.

__**<span style="color: #ff7500; font-family: 'Palatino Linotype','Book Antiqua',Palatino,serif; font-size: 170%; line-height: 27px;">Ecological niche of the Echinoderm **__
 * Definition: The ecological niche is the role that the echinoderm plays in its ecosystem.


 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Contributions to the ecosystem:


 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Sea urchins reduce the rate of colonization of bare rock by grazing, starfish prevent the growth of algal mats on coral reefs which can block filter-feeding constituent organisms. Echinoderms are staple


 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 120%;">Echinoderms are efficient scavengers of decaying matter on the seafloor, and they prey upon a variety of small organisms, thereby helping to regulate their numbers. When present in large numbers, sea urchins can devastate sea-grass beds in the tropics, adversely affecting the organisms dwelling within. Sea urchins that burrow into rocks and along a shore can accelerate the erosion of shorelines. Other tropical species of sea urchins, however, control the growth of seaweeds in coral reefs, thereby permitting the corals to flourish. Removal of the sea urchins results in the overgrowth of seaweeds and the devastation.


 * __<span style="color: #7700ff; font-family: 'Times New Roman',Times,serif; font-size: 170%;">References __**


 * ** Bird, Jonathan. "Echinoderms: The Spiny Animals!" __Oceanic Research Group.__ ED. Jonathan Bird. 5 June 2007. 22 February 2011. [] **


 * ** "Echinoderm." Encyclopedia Britannica. Encyclopedia Britannica Online. Encyclopedia Britannica, 2011. Web. 17 Feb. 2011. <[]>. **


 * Fankboner, Peter V. "Laboratory XI- Echinodermata II." __sfu.com.__ Ed. Peter Fankboner. 1997-2001. 24 February 2011. []


 * ** __Forces of Change.__ Smithsonian Institute. 22 February 2011. [] **
 * ** __Hawaii Coral Reef Network.__ Ed: 25 January 2005. 24 February 2011. [] **


 * ** Moroukian, Paul. Personal Interview. 17 January 2011. **
 * ** Ramel, Gordon. "The Phylum Echinodermata." __Earthlife Web Chapters.__ Ed. Gordon Ramel. 24 February 2011. **** [] **
 * ** Zubi, Teresa. "Invertebrates, Multi-celled animals (Metazoa), Echinoderms." __Starfish.__ Ed. Teresa Zubi. 13 March 2010. 24 February 2011. [] **