Great white sharks, (Carcharodon carcharias), also known as white sharks, are the largest predatory fish in the world. They belong to a partially "warm-blooded" family of sharks called Lamnidae, or mackerel sharks, that are able to maintain an internal body temperature that's warmer than their external environment — unlike other "cold-blooded" sharks, which can't, according to the Florida Museum of Natural History (opens in new tab).
Great white sharks are the only living members of the genus Carcharodon — inspired by the Greek words "karcharos," which means sharpen, and "odous," which means teeth. This name is well-chosen, as great white sharks have rows of up to 300 serrated, triangular teeth. These sharks have bullet-shaped bodies, gray skin and white bellies.
Despite being one of the best-known shark species thanks to movies such as "Jaws" (1975), great white sharks live a secretive lifestyle, and scientists still have much to learn about these iconic predators.
How big are great white sharks?
Great white shark size varies, but females can grow to be larger than males. Female great white sharks reach an average length of 15 to 16 feet (4.6 to 4.9 meters), while males usually reach 11 to 13 feet (3.4 to 4 m), according to the Smithsonian National Museum of Natural History (opens in new tab) in Washington D.C. The largest great white sharks can grow to 20 feet long (6.1 m), and there are unconfirmed reports of great whites growing to 23 feet long (7 m), according to the Florida Museum of Natural History (opens in new tab). Adults weigh between 4,000 and 7,000 pounds (1,800 and 3,000 kilograms), according to the World Wildlife Fund (opens in new tab) (WWF).
Great whites are not the biggest sharks in the world. That title goes to whale sharks (Rhincodon typus), which are filter-feeders and usually grow up to 33 feet (10 m) long and weigh around 42,000 pounds (19,000 kg). The biggest shark species ever was the now-extinct megalodon (Carcharocles megalodon), which may have grown up to 60 feet long (18 m) or more, although scientists are still debating its exact size.
Where are great white sharks found?(opens in new tab)
Great white sharks have a large geographic range; they live in most temperate and tropical oceans around the world and have resident populations off the coasts of the U.S., Australia, South Africa and other countries. They are most often sighted in cooler, temperate waters and swim at the surface as well as down to more than 3,900 feet (1,200 m) below the surface, according to the International Union for Conservation of Nature (opens in new tab) (IUCN).
Genus & species: Carcharodon carcharias
Great white sharks are migratory and undertake long-distance journeys across the open ocean, possibly for food and breeding. A 2002 study published in the journal Nature (opens in new tab) found that one great white shark swam 2,360 miles (3,800 kilometers) from the coast of central California to the Hawaiian island of Kahoolawe. In 2005, researchers tracked a great white shark swimming almost 6,900 miles (11,100 km) from the coast of South Africa to Australia, before later heading back again, Mongabay reported (opens in new tab). To have enough energy for such long journeys, great white sharks store energy in their oil-rich livers, according to the Monterey Bay Aquarium (opens in new tab).
Are great white sharks dangerous?
Great white sharks occasionally bite and kill humans, although the relative risk of being bitten by any shark is very low. A 2021 study published in the Journal of the Royal Society Interface (opens in new tab) found that to a juvenile great white shark, the shape and motion of humans swimming or paddling on surfboards looks the same as seals — one of their main sources of food. This suggests attacks could be a case of mistaken identity, at least for juveniles.
"White sharks are often portrayed as 'mindless killers' and 'fond of human flesh,' however, this does not seem to be the case, we just look like their food," Laura Ryan, lead author of the 2021 study and a postdoctoral researcher at Macquarie University in Australia, previously told Live Science.
When someone has been bitten by a shark, experts often find it difficult to establish which shark species was involved. Sharks don't hang around for identification, and victims can struggle to make an accurate observation of the shark in the heat of the moment. Many shark species also create similar-looking wounds. Shark attack data is therefore skewed towards easily identified species such as great white sharks, according to the Florida Museum of Natural History's International Shark Attack Files (opens in new tab) (ISAF). The ISAF data show there have been 354 unprovoked great white shark attacks, including 57 fatal encounters, recorded since 1580 — more than any other shark species.
What do great white sharks eat?(opens in new tab)
Great white sharks are apex predators that eat a variety of prey, including fish, seals, sea turtles and seabirds. They typically eat smaller prey such as squids and stingrays when they are younger and then shift to eating marine mammals such as seals, sea lions and dolphins once they mature, according to the Australian Museum (opens in new tab) in Sydney.
Great white sharks use quick bursts of speed to catch prey. Thanks to their streamlined bodies, they can race through the water at speeds of up to 15 mph (24 km/h), according to National Geographic (opens in new tab).
By hunting prey, great white sharks and other sharks play an important role in the ocean. They keep prey populations healthy by catching weak and sick individuals and prevent those populations from growing too large for a habitat's resources to support, Live Science previously reported. Great white sharks can also be prey themselves, but their risk of predation drops as they get older and larger. The only things that eat adult great white sharks are larger adult great whites and killer whales (Orcinus orca), which may hunt great whites for their energy-rich livers.
How do great white sharks breed?
Scientists still have plenty to learn about great white sharks, and much of their mating behavior remains a mystery. Researchers have interpreted some bite marks observed on mature female sharks as mating scars, which are caused by males grabbing females during mating, according to the Florida Museum of Natural History.
Scientists have studied shark specimens, such as accidentally caught pregnant females, and know that great white sharks don't lay eggs. Fertilized eggs hatch inside a female's body and develop there until the female gives birth. A 2016 study published in the journal Biology Open (opens in new tab) found that embryos probably feed on uterine fluid and undeveloped eggs between when they hatch inside the mother and when they are born. While in their mother's womb, young great whites also swallow their own teeth, according to the Florida Museum of Natural History. They may do this to reutilize calcium and other minerals.
Scientists assume that great white sharks give birth in warm temperate and tropical waters, but they have not identified specific shark nurseries. Gestation is thought to take about a year, after which a female gives birth to between two and 10 offspring called pups, according to the University of Michigan's Animal Diversity Web (opens in new tab). Pups are more than 3 feet (1 m) long when they are born and are able to take care of themselves.
A 2014 study published in the journal PLOS One (opens in new tab) estimated great white sharks' lifespan based on radiocarbon levels in their vertebrae tissue. The researchers suggested that the oldest female shark in the study was 40 years old and the oldest male was 73 years old. This suggests that males may live longer than females, but further research is needed to corroborate these findings.
Are great white sharks endangered?
Great white sharks are vulnerable to extinction and their population is decreasing, according to a 2018 assessment (opens in new tab) by the IUCN. This means that while these sharks are not technically endangered yet, they are at risk of becoming endangered unless their situation improves. The IUCN didn't have enough data to estimate great white sharks' total population size.
Great white sharks are threatened globally as bycatch — animals caught by fishers that are not the intended target. Great white sharks are also deliberately killed by humans as part of beach-protection programs in Australia and South Africa, although sharks are sometimes captured and released alive.
To learn more about why great white sharks are scarcely seen in captivity and how the Monterey Bay Aquarium was able to briefly display them, watch this short YouTube video by Vox (opens in new tab). For more information about shark attacks and how to avoid them, check out the International Shark Attack Files (opens in new tab) website. For a general guide to the world's sharks, check out "Sharks of the World: A Complete Guide (opens in new tab)" (Princeton University Press, 2021), available to buy at Amazon.
Boustany et al. "Expanded niche for white sharks," Nature, Volume 415, Jan. 3, 2002. https://www.nature.com/articles/415035b (opens in new tab)
Chewning, D. and Hall, M. Animal Diversity Web, "Carcharodon carcharias," 2009. https://animaldiversity.org/accounts/Carcharodon_carcharias/ (opens in new tab)
Florida Museum of Natural History, "Shark Biology," Aug. 9, 2021. https://www.floridamuseum.ufl.edu/discover-fish/sharks/shark-biology/ (opens in new tab)
Hamady et al. "Vertebral bomb radiocarbon suggests extreme longevity in white sharks," PLOS One, Volume 9, Jan. 8, 2014. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0084006 (opens in new tab)
International Shark Attack Files, Florida Museum of Natural History, "Species Implicated in Attacks," updated Jan. 25, 2022. https://www.floridamuseum.ufl.edu/shark-attacks/factors/species-implicated/ (opens in new tab)
Martins, C. and Knickle, C. Florida Museum of Natural History, "Carcharodon carcharias," updated Oct. 18, 2018. https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/carcharodon-carcharias/ (opens in new tab)
McGrouther, M., Australian Museum, "White Shark, Carcharodon carcharias (Linnaeus, 1758)," March 5, 2020. https://australian.museum/learn/animals/fishes/white-shark-carcharodon-carcharias-linnaeus-1758/ (opens in new tab)
Monterey Bay Aquarium, "White shark." https://www.montereybayaquarium.org/animals/animals-a-to-z/white-shark (opens in new tab)
National Geographic, "Great white sharks." https://www.nationalgeographic.com/animals/fish/facts/great-white-shark (opens in new tab)
Pester, P., Live Science, "Great white sharks can't see a difference between humans and prey," Oct. 27, 2021. https://www.livescience.com/great-white-shark-mistaken-identity (opens in new tab)
Rigby et al. The IUCN Red List of Threatened Species, "Carcharodon carcharias," 2019. https://www.iucnredlist.org/species/3855/2878674 (opens in new tab)
Ryan et al. "A shark's eye view: testing the 'mistaken identity theory' behind shark bites on humans," Journal of the Royal Society Interface, Volume 18, Oct. 27, 2021. https://royalsocietypublishing.org/rsif/doi/10.1098/rsif.2021.0533 (opens in new tab)
Sato et al. "How great white sharks nourish their embryos to a large size: evidence of lipid histotrophy in lamnoid shark reproduction," Biology Open, Volume 5, Sep. 15, 2016. https://journals.biologists.com/bio/article/5/9/1211/1210/How-great-white-sharks-nourish-their-embryos-to-a (opens in new tab)
Smithsonian National Museum of Natural History, "How Big are Great White Sharks?" https://ocean.si.edu/ocean-life/sharks-rays/how-big-are-great-white-sharks (opens in new tab)
Weisberger, M., Live Science, "What If There Were No Sharks?" Sep. 9, 2019. https://www.livescience.com/what-if-no-sharks.html