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The great white shark (Carcharodon carcharias), also known as the great white, white shark or white pointer, is a species of large mackerel shark which can be found in the coastal surface waters of all the major oceans. The great white shark is notable for its size, with larger female individuals growing to 6.1 m in length and 1905 kg in weight at maturity. However, most are smaller; males measure 11 to 13 ft, and females measure 15 to 16 ft on average. According to a 2014 study, the lifespan of great white sharks is estimated to be as long as 70 years or more, well above previous estimates, making it one of the longest lived cartilaginous fish currently known. According to the same study, male great white sharks take 26 years to reach sexual maturity, while the females take 33 years to be ready to produce offspring. Great white sharks can swim at speeds of over 56 km/h, and can swim to depths of 1200 m.

The great white shark has no known natural predators other than, on very rare occasions, the killer whale. 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 responsible for more recorded human bite incidents than any other shark.

The species faces numerous ecological challenges which has resulted in international protection. The IUCN lists the great white shark as a vulnerable species, and it is included in Appendix II of CITES. It is also protected by several national governments such as Australia (as of 2018).

The novel Jaws by Peter Benchley and its subsequent film adaptation by Steven Spielberg depicted the great white shark as a "ferocious man eater". Humans are not the preferred prey of the great white shark, but the great white is nevertheless responsible for the largest number of reported and identified fatal unprovoked shark attacks on humans.

Etymology
The English name 'white shark' and its Australian variant 'white pointer' is thought to have come from the shark's stark white underside, a characteristic feature most noticeable in beached sharks lying upside down with their bellies exposed. Colloquial use favours the name 'great white shark', with 'great' perhaps stressing the size and prowess of the species, and "white shark" having historically been used to describe the much smaller oceanic white-tipped shark, later referred to for a time as the "lesser white shark". Most scientists prefer 'white shark', as the name "lesser white shark" is no longer used, while some use 'white shark' to refer to all members of the Lamnidae.

The scientific genus name Carcharodon literally means "jagged tooth", a reference to the large serrations that appear in the shark's teeth. It is a portmanteau of two Ancient Greek words: the prefix carchar- is derived from κάρχαρος (kárkharos), which means "jagged" or "sharp". The suffix -odon is a romanization of ὀδών (odṓn), a which translates to "tooth". The specific name carcharias is a Latinization of καρχαρίας (karkharías), the Ancient Greek word for shark. The great white shark was one of the species originally described by Carl Linnaeus in his 1758 10th edition of Systema Naturae, in which it was identified as an amphibian and assigned the scientific name Squalus carcharias, Squalus being the genus that he placed all sharks in. By the 1810s, it was recognized that the shark should be placed in a new genus, but it was not until 1838 when Sir Andrew Smith coined the name Carcharodon as the new genus.

There have been a few attempts to describe and classify the great white before Linnaeus. One of its earliest mentions in literature as a distinct type of animal appears in Pierre Belon's 1553 book De aquatilibus duo, cum eiconibus ad vivam ipsorum effigiem quoad ejus fieri potuit, ad amplissimum cardinalem Castilioneum. In it, he illustrated and described the shark under the name Canis carcharias based on the jagged nature of its teeth and its alleged similarities with dogs. Another name used for the great white around this time was Lamia, first coined by Guillaume Rondelet in his 1554 book Libri de Piscibus Marinis, who also identified it as the fish that swallowed the prophet Jonah in biblical texts. Linnaeus recognized both names as previous classifications.

Taxonomy and evolution
The great white is the sole recognized extant species in the genus Carcharodon, and is one of five extant species belonging to the family Lamnidae. Other members of this family include the mako sharks, porbeagle, and salmon shark. The family belongs to the Lamniformes, the order of mackerel sharks.

Phylogeny
The modern clade of the Lamnidae is estimated to have emerged between 65 to 46 million years ago (mya) based on a 1996 molecular clock. Most phylogenetic analyses based on mitochondrial DNA place the great white shark as the sister species to the mako shark clade with the Lamna clade as the most basal in the family. Under this topology, the 1996 clock estimated the great white shark's divergence from the makos to have occurred between 60 to 43 mya. A minority of analyses recovered an alternate placement of the great white shark as the most basal member.

Fossil history
The great white shark first unambiguously appears in the fossil record in the Pacific basin about 5.3 mya at the beginning of the Pliocene. Although there are few reports of fossils dated as early as 16 mya, their validity is generally doubted as mislabeled or misidentified. Like all sharks, the great white's skeleton is made primarily of soft cartilage that does not preserve well. The overwhelming majority of fossils as a result are teeth. Nevertheless, paleontologists have confidently traced the emergence of the great white shark and its immediate ancestry to a large extinct shark known as Carcharodon hastalis (alternatively Cosmopolitodus hastalis). This species appeared worldwide during the Late Oligocene (~28 mya) and had teeth alike to the modern great white shark's, except that the cutting edges were non-serrated. The form was derived from an ancient Tethys-Atlantic lineage of large white sharks that arose in the early Eocene (~56-48 mya) from a primitive mako-like shark. C. hastalis occupied a middle to high trophic position in its ecosystems, with a distinct narrow-toothed form that probably specialized in fish and a broad-toothed form that fed on marine mammals.

Around 8 mya, a Pacific stock of C. hastalis evolved into C. hubbelli. This divergent lineage, sometimes described as a chronospecies, was characterized by a gradual development of serrations over the next few million years. They were initially fine and sparse but a mosaic of fossils throughout the Pacific basin document an increase in quantity and coarseness over time, eventually becoming fully serrated as the great white shark's by 5.3 mya. Serrations are more effective at cutting prey than non-serrated edges, facilitating further specialization towards a mammal diet. The ecological circumstances for this innovation may depend on which C. hastalis form was the immediate ancestor of C. hubbelli, which remains uncertain. A narrow-toothed progenitor would imply serrations evolved to accommodate a change in diet, while a broad-toothed ancestor suggests development as a competitive advantage. In addition, teeth from the same strata may exhibit significant variation in serration development and morphology, which may be indicative of persistent interbreeding with C. hastalis for at least some time. The great white shark dispersed as soon as it emerged, with fossils in the Mediterranean, North Sea Basin, and South Africa occurring as early as 5.3-5 mya. Colonization of the northwestern Atlantic may have been delayed, with fossils absent until 3.2 mya. <!-- -great white first appears in pacific, later migrates into atlantic (megalodon extinction paper), although first Mediterranean appearance is 5.3 mya

Molecular clock studies published between 1988 and 2002 determined the closest living relative of the great white to be the mako sharks of the genus Isurus, which diverged some time between 60 and 43 million years ago. Tracing this evolutionary relationship through fossil evidence, however, remains subject to further paleontological study.

The original hypothesis of the great white shark's origin held that it is a descendant of a lineage of mega-toothed sharks, and is closely related to the prehistoric megalodon. These sharks were considerably larger in size, with megalodon attaining an estimated length of up to 14.2 - 20.3 m.  Similarities between the teeth of great white and mega-toothed sharks, such as large triangular shapes, serrated blades, and the presence of dental bands, led the primary evidence of a close evolutionary relationship. As a result, scientists classified the ancient forms under the genus Carcharodon. Although weaknesses in the hypothesis existed, such as uncertainty over exactly which species evolved into the modern great white and multiple gaps in the fossil record, palaeontologists were able to chart the hypothetical lineage back to a 60-million-year-old shark known as Cretalamna as the common ancestor of all sharks within the Lamnidae.

However, it is now understood that the great white shark holds closer ties to the mako sharks and is descended from a separate lineage as a chronospecies unrelated to the mega-toothed sharks. This was proven with the discovery of a transitional species that connected the great white to an unserrated shark known as Carcharodon hastalis. This transitional species, which was named Carcharodon hubbelli in 2012, demonstrated a mosaic of evolutionary transitions between the great white and C. hastalis, namely the gradual appearance of serrations, in a span of between 8 and 5 million years ago. The progression of C. hubbelli characterized shifting diets and niches; by 6.5 million years ago, the serrations were developed enough for C. hubbelli to handle marine mammals. Although both the great white and C. hastalis were known worldwide, C. hubbelli is primarily found in California, Peru, Chile, and surrounding coastal deposits, indicating that the great white had Pacific origins. C. hastalis continued to thrive alongside the great white until its last appearance around one million years ago and is believed to have possibly sired a number of additional species, including Carcharodon subserratus and Carcharodon plicatilis.

However, Yun argued that the tooth fossil remains of C. hastalis and Great White Shark "have been documented from the same deposits, hence the former cannot be a chronospecific ancestor of the latter." He also criticized that the C. hastalis "morphotype has never been tested through phylogenetic analyses," and denoted that as of 2021, the argument that the modern Carcharodon lineage with narrow, serrated teeth evolved from C. hastalis with a broad, unserrated teeth is uncertain.

Tracing beyond C. hastalis, another prevailing hypothesis proposes that the great white and mako lineages shared a common ancestor in a primitive mako-like species. The identity of this ancestor is still debated, but a potential species includes Isurolamna inflata, which lived between 65 and 55 million years ago. It is hypothesized that the great white and mako lineages split with the rise of two separate descendants, the one representing the great white shark lineage being Macrorhizodus praecursor. -->

Mitochondrial clades and genetic history
The great white shark appears to maintain consistent gene flow in nuclear DNA between all inhabited oceans, suggesting that the species likely represents a singular population at the global scale. There nevertheless exists significant divergence between groups in mitochondrial DNA, which is passed exclusively from the mother, and consequentially metapopulations at the local scale. This is likely due to an instinctive tendency for females to remain in or return to their birthplace, while males are wide-roaming. Other factors may include isolation by distance, founder effects, infrequent long-distance dispersal, and vicariance. Three major mitochondrial clades are known: Molecular clocks indicate that divergence of these clades occurred hundreds of thousands to millions of years ago, although there is no agreement on exact timing. Clocks calibrated by Andreotti et al. (2016) using vicariant geological events estimated that the Indo-Pacific and Atlantic clades diverged between 2.58-4.17 mya, while the Atlantic and SAHapD clades diverged between 420-680 kya. An alternative clock calibrated by Leone et al. (2020) using alleged earliest fossils dated to ~11 mya estimated divergence times between the Indo-Pacific clade and the Atlantic and SAHapD clades at 11.13 mya. The Atlantic clade has significantly lower genetic diversity than the Indo-Pacific clade. This may have arose via the founder effect, which implies the former originated from Indo-Pacific migrants. Diversity in South Africa is even lower; the additional occurrence of at least two distinct clades points to repeat bottlenecks and re-colonizations following climate change cycles.
 * Indo-Pacific, representing populations in the northeastern Pacific, Australia, Oceania, and the Mediterranean Sea
 * Atlantic, endemic to the Atlantic Ocean, South Africa, and southern Australia
 * South African haplotype D (SAHapD), which is isolated to South Africa

The existence of an Indo-Pacific population in the Mediterranean Sea, thousands of miles from the clade's typical range, is the result of a long-distance founder event. One hypothesis for this occurrent is the antipodean dispersal hypothesis, proposed by Gubili et al. (2010). It postulates that the population originated as a group of Australian or New Zealander sharks that accidently wandered into the Mediterranean through an unusually powerful Agulhas Current during the Pleistocene. The proposed time of Mediterranean divergence was around 450 kya, which coincided with a period when the current's westward eddies may have traveled farther north due to climate instability. A competing hypothesis is the Pliocene colonization hypothesis, postulated by Leon et al. (2020). It suggests that the Mediterranean population instead diverged around 3.23 mya, and originated from a Pacific population that migrated into the Atlantic through the Central American Seaway.

Skeletal anatomy
"Stable-isotope analyses suggest that some females do not undergo an ontogenetic dietary shift and can show consistent dietary specializa-tion instead"

Communication
Great white sharks communicate with each other through a complex array of body language.

In the former clans around Seal Island, South Africa, great white sharks used several body languages to determine hierarchy.

Several forms of body language are employed to avoid intraspecific violence.

Tail slapping is engaged between two great white sharks to resolve disputes over ownership of prey. Here, one shark lifts its tail out of the water and forcibly slaps the surface to splash water at the competing shark. The competitor either withdraws or responds with tail slaps of its own. Usually one or two tail slaps are exchanged per shark, but some individuals may perform up to fourteen slaps. The prey is conceded to the shark with the most tenacious slapping, which appears to be determined through a cumulative signal strength of tail slapping vigor and frequency. Larger body size does not necessarily secure the superior signal strength; on occasion the smaller shark can emerge victorious. Great white sharks have also been observed to employ tail slapping to intimidate tiger sharks around a whale carcass, and against boats and shark cages, which were likely perceived as competitors.

Human interactions
"In California, peaceful encounters between beachgoers and juvenile great white sharks occur on a near-daily basis."

Books

 * The Devil's Teeth by Susan Casey.
 * Close to Shore by Michael Capuzzo about the Jersey Shore shark attacks of 1916.
 * Twelve Days of Terror by Richard Fernicola about the same events.