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LOPHOPHORE The lophophore is a characteristic feeding organ possessed by four major groups of animals: the Brachiopoda



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LOPHOPHORE

The lophophore is a characteristic feeding organ possessed by four major groups of animals: the Brachiopoda, Bryozoa, Entoprocta, and Phoronida. All lophophores are found in aquatic organisms. It can most easily be described as a ring of ciliated tentacles surrounding the mouth, but it is often horseshoe-shaped or coiled. Phoronids have their lophophores in plain view, but the valves of brachiopods must be opened wide to get a good view of their lophophore.




Why do we call these tentacles a lophophore? Because these tentacles have several distinctive characteristics that differentiate them from the tentacles of other animals. First, these tentacles are hollow. Hollow cavities in the bodies of animals (except for the gut) are called coeloms: for all brachiopods, phoronids and bryozoans, the hollow cavity in the lophophore is the second of the three divisions of the coelom in the entire body. Furthermore, the mouth is always located inside the lophophore ring of tentacles, while the anus lies outside the ring. Finally, the lophophore tentacles are covered with cilia in a specific arrangement that are responsible for generating a current of water that flows toward the mouth.
SHECK EXLEY

Perhaps no other diver holds the imagination of fellow divers as Sheck Exley.  No other diver is so instantly recognisable by simply using his first name: "Sheck".  In his book, Diving Into Darkness (also published under the title Raising the Dead), Philip Finch said "Exley's status in the sport is almost impossible to overstate."

In the field of cave diving, Sheck Exley wrote the book, both figuratively and then literally, when he published Basic Cave Diving: A Blueprint for Survival.  He was the first man to log 1,000 cave dives, at the relatively tender age of 23.  He set, and then repeatedly broke, his own world records for cave penetration, finally settling with a mark of 10,939 feet into the Cathedral, Florida on 16 December 1989.  The title of his autobiography, borrowed from Coleridge, showed his true love: Caverns Measureless to Man.

However, Exley may be better remembered for his accomplishments as a deep diver.  He set the world depth record on various occasions, and at one stage his accomplishments were so far ahead of other deep divers that Bret Gilliam wrote in Deep Diving that "Exley could compete only with himself."  In 1988 he set a world record with a 780 feet dive.  In 1989 he broke that record with a dive to 867 feet.  Four years later he would nearly break that record with a dive to 863 feet.  He was one of only a handful of divers who survived a dive to 400 feet using only compressed air.

Ultimately, it would be another attempt to set a world depth record which would cost Exley his life.  On 6 April 1994, whilst trying to dive to over 1,000 feet with his friend and colleague, Jim Bowden, Sheck Exley died. 

FISH, GILLS & SHARKS

Fish normally have one pair of gill openings. Sharks have 5, 6, or 7 pair of gill openings. These gill openings will be located on the sides of the head. (The flat, bottom dwelling angel sharks gills are an exception.) Skates and rays will have their multiple gill openings on the underside. There are approximately 460 species of sharks around the world. Most of them have five pairs of gill openings. Only a total of 7 shark species out of 460, have 6 or 7 pair of gill openings.


RED CRABS OF CHRISTMAS ISLAND

Red Crabs are famous for their migration from Christmas Island to the sea. Look at the following videos: http://animal.discovery.com/tv-shows/other/videos/fooled-by-nature-christmas-island-crab-migration.htm, http://www.youtube.com/watch?v=LNKgh6TfWXo

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