The great white shark (Carcharodon carcharias), also known as the great white, white pointer, white shark, or white death, is a species of large lamniform shark which can be found in the coastal surface waters of all the major oceans. The great white shark is mainly known for its size, with mature individuals growing up to 6.4 m (21 ft) in length (although reports have been published of great white sharks measuring over 8 m (26 ft), and 3,324 kg (7,328 lb) in weight). This shark reaches its maturity around 15 years of age and was previously believed to have a life span of over 30 years. The true lifespan of Great white sharks is far longer; now estimated to be as long as 70 years or more, making it one of the longest lived cartilaginous fish currently known. Great white sharks can accelerate to speeds that exceed 56 km/h (35 mph).
The great white shark is an apex predator of the seas and has no natural predators. The great white shark is arguably the world's largest known extant macropredatory fish, and is one of the primary predators of marine mammals. It is also known to prey upon a variety of other marine animals, including fish and seabirds. It is the only known surviving species of its genus Carcharodon, and is ranked first in having the most attacks on humans. The IUCN list the great white shark as a vulnerable species, while it is included in Appendix II of CITES.
The bestselling novel Jaws by Peter Benchley and the subsequent blockbuster film by Steven Spielberg depicted the great white shark as a "ferocious man eater". In reality, humans are not the preferred prey of the great white shark, however of all shark species, the great white shark is responsible for by far the largest number of fatal unprovoked attacks on humans.
Shark attacks
Of all shark species, the great white shark is responsible for by far the largest number of recorded shark attacks on humans, with 272 documented unprovoked attacks on humans in which the great white shark was identified as of 2012.
More than any documented attack, Peter Benchley's best-selling novel Jaws and the subsequent 1975 film adaptation directed by Steven Spielberg provided the great white shark with the image of being a "man eater" in the public mind. While great white sharks have killed humans in at least 74 documented unprovoked attacks in which the species was identified, they typically do not target them: for example, in the Mediterranean Sea there have been 31 confirmed attacks against humans in the last two centuries, most of which were non-fatal. Many of the incidents seemed to be "test-bites". Great white sharks also test-bite buoys, flotsam, and other unfamiliar objects, and they might grab a human or a surfboard to identify what it is.
The great white shark is one of only four kinds of sharks that have been involved in a significant number of fatal unprovoked attacks on humans.
Other incidents seem to be cases of mistaken identity, in which a shark ambushes a bather or surfer from below, believing the silhouette is from a seal. Many attacks occur in waters with low visibility or other situations which impair the shark's senses. The species appears to not like the taste of humans, or at least finds the taste unfamiliar. Further research shows that they can tell in one bite whether or not the object is worth attacking. Humans, for the most part, are too bony for their liking. They much prefer a fat, protein-rich seal.
However, some researchers have hypothesized that the reason the proportion of fatalities is low is not because sharks do not like human flesh, but because humans are often able to escape after the first bite. In the 1980s John McCosker, the Chair of Aquatic Biology at California Academy, noted that divers who dove solo and were attacked by great whites were generally at least partially consumed, while divers who followed the buddy system were generally rescued by their buddy. McCosker and Timothy C. Tricas, an author and professor at the University of Hawaii, suggest that a standard pattern for great whites is to make an initial devastating attack and then wait for the prey to weaken before consuming the wounded animal. Humans' ability to move out of reach with the help of others, thus foiling the attack, is unusual for a great white's prey.
Humans are not appropriate prey because the shark's digestion is too slow to cope with a human's high ratio of bone to muscle and fat. Accordingly, in most recorded attacks, great whites broke off contact after the first bite. Fatalities are usually caused by blood loss from the initial bite rather than from critical organ loss or from whole consumption. From 1990 until 2011 there have been a total of 139 unprovoked great white shark attacks, 29 fatal.
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