| MadSci Network: Zoology |
Hi John, Shark's teeth are normally replaced every eight days. An average shark goes through 30,000 teeth in their lifetime. This link is a really good shark page!! There are shark facts and information, myths, shark gods,shark attacks, shark links, resources, legends. Check it out! http://www.mauigateway.com/~lechler/Sharks.htm http://www.angelfire.com/nj/jimmyray/jrsharkc.html http://venice-fla.com/sharky.htm The great white shark is probably the most famous of all the sharks. It belongs to a family of fast-swimming sharks called mackerel sharks and is the largest carnivorous, or meat eating fish on earth today, excluding plankton-eaters. The largest white shark on record was 6.4 meters (21 feet) long and weighed 3312 kilograms (7302 pounds). Its ancestors, now extinct, were three times this size, with teeth that were 16 centimeters (6 inches) long! Named for their white undersides and large size, white sharks can also be identified by the shape of their teeth, if you care to venture that close! Narrow teeth lie in the front of the bottom jaw and are used to grab and hold prey. Serrated triangle-shaped teeth are in the top row and are used for cutting. Behind this front row of teeth lie many other rows, with each tooth ready to pop into place when the one in front of it is lost. The rough edges help the teeth cut more easily. After grabbing a whole fish or part of a large animal with their teeth, the shark carries the prey deep underwater until it bleeds to death and then swallows it whole. Because they can swim at high speeds, white sharks are able to feed on fast-moving prey like tuna, seals, sea lions, and even other sharks. White sharks are ovoviviparous, which means that they hold eggs inside of their bodies until the young are ready to hatch. The babies, or pups, are born alive, fully formed and ready to hunt for food. White shark pups may be 1.4 meters (4.5 feet) long at birth and have a full set of teeth. A wide-ranging shark, the white shark makes its home in both the Atlantic and Pacific oceans, from the tropics to the icecaps. This shark is usually found in deeper water over the continental shelf, a flat part of a submerged continent which drops off to the ocean floor. However, a white shark will occasionally wander into shallow water quite close to shore where it finds most of its food. The white shark's eye structure is well suited for daytime vision and most attacks occur during the day at high tide. People consider it one of the most dangerous sharks because of its large size, aggressive behavior, and habit of swimming into shallow water. Bathers and divers have been attacked by this shark, but it is neither as mean or as common as the movie Jaws would have you believe. Some divers have even reported it as a shy creature that swims away when approached. Recent research has also shown that the white shark often rejects humans as a suitable food source. Humans have been bitten by white sharks and then spit out, or left alone. White sharks have a preference for fatty, energy rich food, and so a skinny human doesn't compare to a blubbery elephant seal. Even so, the white shark is a fish to be respected and avoided! The number of white sharks has dwindled in recent years and so conservation of this animal has become a new concern. So far, California, South Africa, and Australia have passed laws to protect these fascinating creatures from life threatening encounters with misplaced nets and thoughtless trophy hunters. Hopefully, more nations will join to protect the great white shark so scientists can continue to study their unique behaviors. http://www.aqua.org/animals/species/whitshark.html Hope that takes care of your question,,, June Wingert, Mad Scientist
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