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| Great White Shark
Vulnerable
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| Scientific classification | ||||||||||||||||
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| Binomial name | ||||||||||||||||
| Carcharodon carcharias (Linnaeus, 1758) |
Great Whites have excellent eyesight and can see in color, and have highly-developed behaviors which are only now being researched. Their reputation as ferocious predators is well-earned, yet they are not (as once was believed) indiscriminate 'eating machines.' Great White sharks primarily eat fishes and pinnipeds such as seals and sea lions. The only animals known to attack them are other Great Whites, Sperm Whales, humans and orcas.
While the Great White has been responsible for many fatalities in humans, it doesn't target humans as prey. Many incidents seem to be caused by the animals 'test-biting' out of curiosity, as they are known to do with buoys, flotsam, and other unfamiliar objects -- grabbing a human or a surfboard with their mouth, their only tactile organ, in order to determine what kind of object it might be. Other incidents seem to be cases of mistaken identity, in which a shark ambushes a bather or surfer, usually from below, believing the silhouette it sees on the surface is a seal. Humans, in any case, aren't good for Great White sharks to eat, because the sharks' digestion is too slow to cope with the human body's high ratio of bone to muscle and fat. Accordingly, in nearly all recorded attacks, Great Whites have broken off contact after the first bite. Fatalities are caused by loss of blood from the initial injury. Most attacks also occur in waters with low visibility, or in other cases in which the shark's senses are impaired.
Many "shark repellents" have been tested, some using smell, others using protective clothing, but to date the most effective is an electronic beacon worn by the diver/surfer that emits a high frequency signal disturbing to the shark's elecromagnetic sensors.
Great Whites, like many other sharks, have rows of teeth behind the main ones, allowing any that break off to be replaced rapidly. Their teeth are unattached to the jaw and are retractable, like a cat's claws, moving into place when the jaw is opened. This arrangement also seems to give their teeth high tactile sensitivity.