Coral

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Alcyonaria    Alcyonacea    Helioporacea Zoantharia    Antipatharia    Corallimorpharia    Scleractinia    Zoanthidea   See Anthozoa for details

Corals are marine organisms from the class Anthozoa and exist as small sea anemone-like polyps, typically in colonies of many identical individuals. The group includes the important reef builders that are found in tropical oceans, which secrete calcium carbonate to form a hard skeleton.

A coral "head", commonly perceived to be a single organism, is formed from myriads of individual but genetically identical polyps, each polyp only a few millimeters in diameter. Over thousands of generations, the polyps lay down a skeleton that is characteristic of their species. An individual head of coral grows by asexual reproduction of the individual polyps. Corals also breed sexually by spawning, with corals of the same species releasing gametes simultaneously over a period of one to several nights around a full moon.

Although corals can catch small fish and animals such as plankton using stinging cells on their tentacles, these animals obtain most of their nutrients from photosynthetic unicellular algae called zooxanthellae. Consequently, most corals depend on sunlight and grow in clear and shallow water, typically at depths shallower than 60 m (200 ft). These corals can be major contributors to the physical structure of the coral reefs that develop in tropical and subtropical waters, such as the enormous Great Barrier Reef off the coast of Queensland, Australia. Other corals do not have associated algae and can live in much deeper water, with the cold-water genus Lophelia surviving as deep as 3000 m. Examples of these can be found living on the Darwin Mounds located north-west of Cape Wrath, Scotland. Corals have also been found off the coast of Washington State and the Aleutian Islands in Alaska.

Corals coordinate behaviour by communicating with each other.

For more information about Coral, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with coral

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Red Sea coral seen to feed on jellyfish

Red Sea coral seen to feed on jellyfish

Biology / Plants & Animals

created Nov 17, 2009 | popularity 4.5 / 5 (12) | comments 2

(PhysOrg.com) -- Corals depends on the products of photosynthetic algae for most of their food, but they also eat tiny plankton. Now, for the first time, there is evidence of a coral eating jellyfish.


Sponges recycle carbon to give life to coral reefs

Biology / Plants & Animals

created Nov 13, 2009 | popularity 4.3 / 5 (4) | comments 1

Coral reefs support some of the most diverse ecosystems on the planet, yet they thrive in a marine desert. So how do reefs sustain their thriving populations?


Australian scientists call for urgent 'global cooling' to save coral reefs

Space & Earth / Environment

created Nov 09, 2009 | popularity 1.8 / 5 (5) | comments 2

(PhysOrg.com) -- Australian marine scientists have issued an urgent call for massive and rapid worldwide cuts in carbon emissions, deep enough to prevent atmospheric CO2 levels rising to 450 parts per million (ppm).


Discovery of the Jekyll-and-Hyde factors in 'coral bleaching'

Discovery of the Jekyll-and-Hyde factors in 'coral bleaching'

Space & Earth / Environment

created Dec 02, 2009 | popularity 4.5 / 5 (2) | comments 0

Scientists are reporting the first identification of substances involved in the Jekyll-and-Hyde transformation that changes harmless marine bacteria into killers that cause "coral bleaching." Their study appears ...


Caribbean, Gulf spared widespread coral damage

Space & Earth / Environment

created Nov 06, 2009 | popularity 3 / 5 (2) | comments 1

(AP) -- Lower-than-feared sea temperatures this summer gave a break to fragile coral reefs across the Caribbean and the central Gulf of Mexico that were damaged in recent years, scientists said Thursday.


Calm before the spawn: Climate change and coral spawning

Space & Earth / Environment

created Nov 04, 2009 | popularity 1 / 5 (4) | comments 2

What's the point of setting up marine reserves to protect coral reefs from pollution, ship groundings and overfishing if climate change could cause far more damage? A study published this week in London in Proceedings of ...


Coral reefs inspire rare consensus -- just save them

Coral reefs inspire rare consensus -- just save them

Space & Earth / Environment

created Nov 05, 2009 | popularity 1 / 5 (1) | comments 0

One of the first set of studies to examine what tourists and recreation enthusiasts actually think about coral reef ecosystems suggests they are a rare exception to controversies over human use versus environmental ...


Researchers take part in DNA sequencing for entire Pacific island

Researchers plan DNA sequencing for entire Pacific island

Biology / Plants & Animals

created Dec 02, 2009 | popularity not rated yet | comments 0

(PhysOrg.com) -- University of Florida researchers are collecting marine invertebrates on the French Polynesian island of Moorea as part of a massive effort to inventory the DNA sequence of every living species ...