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2023-09-06 
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Scientists have recently discovered special cells called melanocytes in great white sharks' skin that appear to allow the predator's coloration to lighten or darken. It's thought this ability may lend even more control over their cloaking ability as they sneak up on prey from below.
With bodies shaped like torpedoes and powerful tailfins, great whites can rocket through the water at speeds approaching 35 miles an hour (50 kilometers an hour). This speed and a bite force of up to 1.8 metric tons allow the shark to quickly inflict massive trauma on their prey, disabling their target and thus protecting against a counterattack.
Great white teeth
The great white shark's infamous smile is made up of seven rows of serrated, 2.5-inch-long teeth. While the animals possess around 300 teeth in total, most aren't used to bite. Instead, the teeth are part of a highly efficient, conveyor-belt-like apparatus the sharks have evolved to replace teeth that are lost during daily wear and tear. Unlike humans, which only ever grow two sets of teeth, great whites keep growing new chompers as long as they live.
In some cases, great white sharks have even been documented with whole rows of missing teeth, perhaps as the result of a run-in with a shark cage or some other piece of human-made equipment. Scientists say even in these unlikely scenarios, the sharks' new teeth come in quickly, allowing the animals to once again rise to the upper echelons of the oceanic food chain.
Habitat and diet
While frequently associated with Australia and South Africa, great white sharks tend to be found in temperate and tropical coastal waters all over the planet.
Great white habitat preferences change as they age: Pups and juveniles are more likely to be found in coastal and estuary habitats, and adults usually live farther out at sea in pelagic, or open ocean, ecosystems. However, even large adults will cruise shorelines if there's a known food source, such as a seal or sea lion rookeries.
(Cape Cod may have the highest density of great white sharks in the world.)
Depending on their size and age, great white sharks target crustaceans, mollusks, sea birds, sea turtles, and marine mammals, including sea lions, seals, dolphins, and even some whales. Great whites will also consume prey that has already died, such as the large carcasses of dead whales, using their steak-knife-like teeth to carve off pieces of rotting flesh.
Reproduction
Great white sharks are relatively slow reproducers, which is not surprising given the animals' enormous size. For instance, some estimates suggest females cannot even begin reproducing until at least 30 years of age.
Great white shark mothers give birth to live young once every two or three years. Litters usually consist of between two and 17 pups, each of which can be between four and six feet long. Each pup swims into the world fully capable of hunting and surviving on its own and will grow around 12 inches a year for its first five to six years of life.
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