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The great white shark (Carcharodon carcharias), also known as the white shark, white pointer, or simply great white, is a species of large mackerel shark which can be found in the coastal surface waters of all the major oceans. It is the only known surviving species of its genus Carcharodon. The great white shark is notable for its size, with the largest preserved female specimen measuring 5.83 m (19.1 ft) in length and around 2,000 kg (4,410 lb) in weight at maturity.[3] However, most are smaller; males measure 3.4 to 4.0 m (11 to 13 ft), and females measure 4.6 to 4.9 m (15 to 16 ft) on average.[4][5] 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,[6] making it one of the longest lived cartilaginous fishes currently known.[7] 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.[8] Great white sharks can swim at speeds of 25 km/h (16 mph)[9] for short bursts and to depths of 1,200 m (3,900 ft).[10]

The great white shark is arguably the world's largest-known extant macropredatory fish, and is one of the primary predators of marine mammals, such as pinnipeds and dolphins. The great white shark is also known to prey upon a variety of other animals, including fish, other sharks, and seabirds. It has only one recorded natural predator, the orca.[11]

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The species faces numerous ecological challenges which has resulted in international protection. The International Union for Conservation of Nature lists the great white shark as a vulnerable species,[1] and it is included in Appendix II of CITES.[12] It is also protected by several national governments, such as Australia (as of 2018).[13] Due to their need to travel long distances for seasonal migration and extremely demanding diet, it is not logistically feasible to keep great white sharks in captivity; because of this, while attempts have been made to do so in the past, there are no known aquariums in the world believed to house a live specimen.[14]

The great white shark is depicted in popular culture as a ferocious man-eater, largely as a result of the novel Jaws by Peter Benchley and its subsequent film adaptation by Steven Spielberg. Humans are not a preferred prey,[15] but nevertheless it is responsible for the largest number of reported and identified fatal unprovoked shark attacks on humans.[16] However, attacks are rare, typically occurring fewer than 10 times per year globally.[17][18]

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.[19] Other members of this family include the mako sharks, porbeagle, and salmon shark. The family belongs to the Lamniformes, the order of mackerel sharks.[20]

The English name 'white shark' and its Australian variant 'white pointer'[21] 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.[22] Colloquial use favours the name 'great white shark', with 'great' perhaps stressing the size and prowess of the species,[23] 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,[23] while some use 'white shark' to refer to all members of the Lamnidae.[20]

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.[a] 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.[26] Linnaeus recognized both names as previous classifications.[24]

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.[28][29] Tracing this evolutionary relationship through fossil evidence, however, remains subject to further paleontological study.[29]

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.[29] This was proven with the discovery of a transitional species that connected the great white to an unserrated shark known as Carcharodon hastalis.[34][35] 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,[34] in a span of between 8 and 5 million years ago.[36] 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.[34] Although both the great white and C. hastalis were known worldwide,[29] C. hubbelli is primarily found in California, Peru, Chile, and surrounding coastal deposits,[37] indicating that the great white had Pacific origins.[34] C. hastalis continued to thrive alongside the great white until its last appearance around one million years ago[38] and is believed to have possibly sired a number of additional species, including Carcharodon subserratus[29][34] and Carcharodon plicatilis.[29]

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.[40] 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.[40][41]

Great white sharks live in almost all coastal and offshore waters which have water temperature between 12 and 24 C (54 and 75 F), with greater concentrations in the United States (Northeast and California), South Africa, Japan, Oceania, Chile, and the Mediterranean including the Sea of Marmara and Bosphorus.[42][43] One of the densest-known populations is found around Dyer Island, South Africa.[44] Juvenile great white sharks inhabit a more narrow band of temperatures, between 14 and 24 C (57 and 75 F), in shallow coastal nurseries.[45] Increased observation of young sharks in areas they were not previously common, such as Monterey Bay on the Central California coast, suggest climate change may be reducing the range of juvenile great white sharks and shifting it toward the poles.[46]

The great white is an epipelagic fish, observed mostly in the presence of rich game, such as fur seals (Arctocephalus ssp.), sea lions, cetaceans, other sharks, and large bony fish species. In the open ocean, it has been recorded at depths as great as 1,200 m (3,900 ft).[10] These findings challenge the traditional notion that the great white is a coastal species.[10]

According to a recent study, California great whites have migrated to an area between Baja California Peninsula and Hawaii known as the White Shark Caf to spend at least 100 days before migrating back to Baja. On the journey out, they swim slowly and dive down to around 900 m (3,000 ft). After they arrive, they change behaviour and do short dives to about 300 m (980 ft) for up to ten minutes. Another white shark that was tagged off the South African coast swam to the southern coast of Australia and back within the year. A similar study tracked a different great white shark from South Africa swimming to Australia's northwestern coast and back, a journey of 20,000 km (12,000 mi; 11,000 nmi) in under nine months.[47]These observations argue against traditional theories that white sharks are coastal territorial predators, and open up the possibility of interaction between shark populations that were previously thought to have been discrete. The reasons for their migration and what they do at their destination is still unknown. Possibilities include seasonal feeding or mating.[48]

In the Northwest Atlantic, the white shark populations off the New England coast were nearly eradicated due to over-fishing.[49] In recent years, the populations have grown greatly,[50] largely due to the increase in seal populations on Cape Cod, Massachusetts since the enactment of the Marine Mammal Protection Act in 1972.[51] Currently very little is known about the hunting and movement patterns of great whites off Cape Cod, but ongoing studies hope to offer insight into this growing shark population.[52] The Massachusetts Division of Marine Fisheries (part of the Department of Fish and Game) began a population study in 2014; since 2019, this research has focused on how humans can avoid conflict with sharks.[53]

A 2018 study indicated that white sharks prefer to congregate deep in anticyclonic eddies in the North Atlantic Ocean. The sharks studied tended to favour the warm-water eddies, spending the daytime hours at 450 meters and coming to the surface at night.[54]

The great white shark has a robust, large, conical snout. The upper and lower lobes on the tail fin are approximately the same size which is similar to some mackerel sharks. A great white displays countershading, by having a white underside and a grey dorsal area (sometimes in a brown or blue shade) that gives an overall mottled appearance. The coloration makes it difficult for prey to spot the shark because it breaks up the shark's outline when seen from the side. From above, the darker shade blends with the sea and from below it exposes a minimal silhouette against the sunlight. Leucism is extremely rare in this species, but has been documented in one great white shark (a pup that washed ashore in Australia and died).[55] Great white sharks, like many other sharks, have rows of serrated teeth behind the main ones, ready to replace any that break off. When the shark bites, it shakes its head side-to-side, helping the teeth saw off large chunks of flesh.[56] Great white sharks, like other mackerel sharks, have larger eyes than other shark species in proportion to their body size. The iris of the eye is a deep blue instead of black.[57] 17dc91bb1f