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Great white shark
Temporal range: 16–0 Ma[1] Miocene to Recent
Illustration showing a shark and a human diver. The shark is about three times longer than the human.
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Lamniformes
Family: Lamnidae
Genus: Carcharodon
A. Smith, 1838
Species:
C. carcharias
Binomial name
Carcharodon carcharias
  Global range as of 2010
Synonyms
List of synonyms
    • Canis carcharias Belon, 1553
    • Squalus carcharias Linnaeus, 1758
    • Carharodon carcharias Linnaeus, 1758)
    • Squalus caninus Osbeck, 1765
    • Carcharias lamia Rafinesque, 1810
    • Carcharias verus Cloquet, 1817
    • Squalus vulgaris Richardson, 1836
    • (Carcharias vulgaris Richardson, 1836)
    • Carcharodon smithii Agassiz, 1838
    • Carcharodon smithi Bonaparte, 1838
    • Carcharodon rondeletii Müller & Henle, 1839
    • Carcharodon capensis Smith, 1839
    • Carcharias atwoodi Storer, 1848
    • Carcharias maso Morris, 1898
    • Carcharodon albimors Whitley, 1939

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 (20 ft) in length and 1,905 kg (4,200 lb) in weight at maturity.[3][4][5] 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.[5][6] 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,[7] making it one of the longest lived cartilaginous fish currently known.[8] 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.[9] Great white sharks can swim at speeds of over 56 km/h (35 mph),[10] and can swim to depths of 1,200 m (3,900 ft).[11]

The great white shark has no known natural predators other than, on very rare occasions, the killer whale.[12] 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.[13][14]

The species faces numerous ecological challenges which has resulted in international protection. The IUCN lists the great white shark as a vulnerable species,[2] and it is included in Appendix II of CITES.[15] It is also protected by several national governments such as Australia (as of 2018).[16]

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,[17] but the great white is nevertheless responsible for the largest number of reported and identified fatal unprovoked shark attacks on humans.[18]

Etymology

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The name 'great white shark' likely comes from the shark's size, as well as the white underside exposed on beached sharks.

The English name 'white shark' and its Australian variant 'white pointer'[19] 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.[20] Colloquial use favours the name 'great white shark', with 'great' perhaps stressing the size and prowess of the species,[21] 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,[21] while some use 'white shark' to refer to all members of the Lamnidae.[22]

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.[23] 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.[24] 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.[25]

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]

Taxonomy and evolution

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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.[23] Other members of this family include the mako sharks, porbeagle, and salmon shark. The family belongs to the Lamniformes, the order of mackerel sharks.[22]

Phylogeny

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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 using the mitochondrial DNA gene cytochrome b. 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.[b] A more recent 2024 clock using genome-wide data obtained from target gene capture sequencing[c] estimated a later alternate divergence between the shortfin mako and great white shark at 41.6 mya.[d] A minority of analyses recovered an alternate placement of the great white shark as the most basal member.

Phylogenetic relationships based on whole mitogenome
Topology A with cytochrome b molecular clock by Martin (1996)
Lamniformes

Sand tiger shark

Basking shark

65‑46 mya
60‑43 mya

Great white shark

Topology B
Lamniformes

Fossil history

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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.[e] 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[f]). 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.[g]

Evolution from C. hastalis to C. carcharias

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[h] 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.[27] 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.

Populations and genetic history

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Great white sharks from Indo-Pacific (left) and South African (right) populations

The great white shark as a species does not behave as a unified metapopulation at the global scale

at the global scale The great white shark had long appeared 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:

  • Indo-Pacific, representing populations in the northeastern Pacific, Australia[i], Oceania, and the Mediterranean Sea
  • Atlantic, endemic to the Atlantic Ocean, South Africa, and southern Australia[j]
  • South African haplotype D (SAHapD), which is isolated to South Africa


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[l] 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[k] 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.

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.

Description

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Appearance and coloration

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Skeletal anatomy

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"Stable-isotope analyses suggest that some females do not undergo an ontogenetic dietary shift and can show consistent dietary specializa-tion instead" [33]

Senses

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Regional endothermy

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Hydrodynamics and locomotion

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Ecology and behavior

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Range and distribution

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Feeding

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Diet

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Hunting strategies

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Social behavior

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Clan structures

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Communication

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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 and avoid intraspecific violence.

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.[o] 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 that were likely perceived as competitors.[34]

Life history

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Reproduction

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Growth

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Natural threats

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Orcas

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Parasites and disease

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Relationship with humans

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Human interactions

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

Reasons for incidents

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Shark tourism

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The use of bait, which elicits predatory behavior, to film great white sharks fueled their image as mindless eating machines.[34]

Conservation

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Population

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Threats

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Great whites may have exceeded 7 meters (23 ft) in length during the Pliocene, while today they rarely approach 6 meters (20 ft). This apparent decrease in size was hypothesized to be a consequence of overfishing.

Shark culling

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See also

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Books

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Notes

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  1. ^ During Belon's time, sharks were called "sea dogs".[26]
  2. ^ Martin (1996) is the only study whose molecular clock is widely cited. A second study by López-Romero et al. (2023) used a molecular clock of 90 shark species, including the great white shark, based on 13 mitochondrial and 2 nuclear genes. The great white shark's divergence time was not discussed, but raw outputs from the study's supplementary materials estimate divergence from the mako sharks at 40.82-69.69 mya. 54.1% of the 1,000 sampled phylogenetic trees were constrained to 50.00-55.99 mya.
  3. ^ Not to be confused with whole genome sequencing
  4. ^ Based on an a priori age constraint of 35-60 mya citing Martin (1996); 95% highest posterior density was 30.8-54.7 mya
  5. ^ For example, several Miocene fossils initially identified as great white sharks were later found to be juvenile forms of the contemporaneous megalodon.
  6. ^ The genus name remains subject to esoteric debate that does not significantly affect the consensus on the great white shark's origins in C. hastalis. The debate primarily centers on whether the appearance of serrations is sufficient to delineate separate genera, and whether a form traditionally attributed to C. hastalis is actually a separate species called C. plicatilis. The latter's recognition is necessary for Cosmopolitodus be a natural grouping. This should not be confused with the archaic name Isurus hastalis, which is no longer recognized by paleontologists.
  7. ^ The relationship between the two forms is debated. Some paleontologists consider them to be age or sex-related differences, while other argue that the broad-toothed form represents a separate species, C. plicatilis. Neither hypothesis has been tested through phylogenetic analysis.
  8. ^ California, Peru, Chile, Japan, Australia, and New Zealand
  9. ^ Locally known as the East Australasian population
  10. ^ Locally known as the Southern-western population
  11. ^ a b This is inconsistent with contemporary paleontological consensus of C. carcharias origins, which Leone et al. (2020) overlooked. Reports of fossils predating the C. hubbelli-C. carcharias transition between 8-5 mya are dubious and likely artifacts of mislabeling or misidentifications of similar taxa like megalodon.[32]
  12. ^ a b Closure of the Central American Seaway ~3.5 mya (which severed communication between the east Pacific and Atlantic) and ascent of the Sunda and Sahul shelves ~5 mya (which restricted communication between Pacific and Indian oceans) respectively.
  13. ^ Via target gene capture sequencing of 10,484 single nucleotide polymorphisms throughout the genome; not to be confused with whole genome sequencing.
  14. ^ Via target gene capture sequencing throughout the genome; not to be confused with whole genome sequencing.
  15. ^ This behavior is most extensively studied amongst the pinniped-eating population around Seal Island, South Africa, but has also been observed off Guadalupe Island, Mexico.[34]

References

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  1. ^ Cite error: The named reference CA was invoked but never defined (see the help page).
  2. ^ a b Fergusson, I.; Compagno, L.J.V.; Marks, M. (2009). "Carcharodon carcharias". The IUCN Red List of Threatened Species. 2009: e.T3855A10133872. doi:10.2305/IUCN.UK.2009-2.RLTS.T3855A10133872.en. Retrieved 18 September 2018.
  3. ^ "Great white sharks: 10 myths debunked". The Guardian. Retrieved 3 June 2016.
  4. ^ Carpenter, K. "Carcharodon carcharias". FishBase.org. Retrieved 3 June 2016.
  5. ^ a b Viegas, Jennifer. "Largest Great White Shark Don't Outweigh Whales, but They Hold Their Own". Discovery Channel. Retrieved 19 January 2010.
  6. ^ Parrish, M. "How Big are Great White Sharks?". Smithsonian National Museum of Natural History Ocean Portal. Retrieved 3 June 2016.
  7. ^ "Carcharodon carcharias". Animal Diversity Web. Retrieved 5 June 2016.
  8. ^ "New study finds extreme longevity in white sharks". Science Daily. 9 January 2014.
  9. ^ Ghose, Tia (19 February 2015). "Great White Sharks Are Late Bloomers". LiveScience.com.
  10. ^ Wright, Bruce A. (2007) Alaska's Great White Sharks. Lulu.com. p. 27. ISBN 0-615-15595-2.
  11. ^ Thomas, Pete (5 April 2010). "Great white shark amazes scientists with 4000-foot dive into abyss". GrindTV. Archived from the original on 17 August 2012.
  12. ^ Currents of Contrast: Life in Southern Africa's Two Oceans. Struik. 2005. pp. 31–. ISBN 978-1-77007-086-8.
  13. ^ Knickle, Craig. "Tiger Shark". Florida Museum of Natural History Ichthyology Department. Archived from the original on 7 July 2013. Retrieved 2 July 2009.
  14. ^ "ISAF Statistics on Attacking Species of Shark". Florida Museum of Natural History University of Florida. Archived from the original on 24 April 2012. Retrieved 4 May 2008.{{cite web}}: CS1 maint: unfit URL (link)
  15. ^ "Carcharodon carcharias". UNEP-WCMC Species Database: CITES-Listed Species On the World Wide Web. Archived from the original on 16 June 2013. Retrieved 8 April 2010.
  16. ^ Government of Australia Department of Sustainability, Environment, Water, Population and Communities (2013). Recovery Plan for the White Shark (Carcharodon carcharias) (Report).{{cite report}}: CS1 maint: multiple names: authors list (link)
  17. ^ Hile, Jennifer (23 January 2004). "Great White Shark Attacks: Defanging the Myths". Marine Biology. National Geographic. Archived from the original on 26 April 2009. Retrieved 2 May 2010.
  18. ^ ISAF Statistics on Attacking Species of Shark
  19. ^ "Common names of Carcharodon carcharias". FishBase. Archived from the original on 23 February 2022. Retrieved 8 November 2020.
  20. ^ Martins, C.; Knickle, C. (2018). "Carcharodon carcharias". Florida Museum. Archived from the original on 11 November 2020. Retrieved 8 November 2020.
  21. ^ a b Martin, R. A. "White Shark or Great White Shark?". Elasmo Research. Archived from the original on 22 April 2021. Retrieved 8 November 2020.
  22. ^ a b "Family Lamnidae – Mackerel sharks or white shark". FishBase. Archived from the original on 10 November 2020. Retrieved 9 November 2020.
  23. ^ a b "Carcharodon carcharias, Great white shark". FishBase. Archived from the original on 9 November 2020. Retrieved 8 November 2020.
  24. ^ a b Linnaeus, C (1758). Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata (in Latin). Vol. 1. Holmiae (Laurentii Salvii). p. 235. doi:10.5962/bhl.title.542. Archived from the original on 25 March 2017. Retrieved 8 November 2020.
  25. ^ Jordan, D. S. (1925). "The Generic Name of the Great White Shark, Squalus carcharias L.". Copeia. 140 (1925): 17–20. doi:10.2307/1435586. JSTOR 1435586.
  26. ^ a b Costantino, G. (18 August 2014). "Sharks Were Once Called Sea Dogs, And Other Little-Known Facts". Smithsonain.com. Smithsonian Institution. Archived from the original on 1 July 2019. Retrieved 18 May 2019.
  27. ^ http://naka.na.coocan.jp/escheri.html
  28. ^ a
  29. ^ a
  30. ^ a
  31. ^ a
  32. ^ https://natuurtijdschriften.nl/pub/677433/
  33. ^ https://www.researchgate.net/publication/319155078_The_tooth_the_whole_tooth_and_nothing_but_the_tooth_tooth_shape_and_ontogenetic_shift_dynamics_in_the_white_shark_Carcharodon_carcharias
  34. ^ a b c https://brill.com/view/journals/beh/160/11-14/article-p1103_4.xml
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