They're located on either side of the head, providing a wide field of vision. Great white shark eyesĪ white shark's eyes are relatively large for shark species. In white sharks, the olfactory bulb used to process smells accounts for 18% of total brain mass, the most of any shark species, suggesting that smell is particularly important to them. Studies on species including lemon sharks and bonnethead sharks reveal that they can detect one drop of scent in a billion drops of water at best, which is about the same as any other fish species. This is actually considered an overstatement. You might be familiar with the saying that sharks can 'smell a drop of blood a mile away'. As cool, oxygenated blood headed towards the body passes warm, deoxygenated blood pushed to the gills, the heat transfers and returns to the muscles meaning the shark has more energy for hunting, even in cooler waters. White sharks can also stay warm thanks to a specialised web of capillaries in their swimming muscles known as a 'rete mirabile', which is Latin for 'wonderful net'. This type of colouration is known as countershading. Combined with their grey colouring on top, this works as effective camouflage whether their targets are looking up to the bright sky or down to the sea floor. The name 'white shark' refers to the colour of their bellies. This allows them to move as fast as 40 kilometres per hour (25 miles per hour) in short bursts as they accelerate towards their prey. White sharks have streamlined, torpedo-shaped bodies. They have evolved some amazing adaptations to help them hunt. Great white sharks are apex predators, which means they are at the top of the food chain.
Such flexibility shows these sharks can make the most of whatever feeding opportunities they encounter, and possibly avoid conflict and competition with their own kind.
They also feed on live whales, with scientists revealing the first recorded evidence of a white shark feeding on a humpback whale in 2020. Both adults and juveniles will also scavenge from fishing nets and dead whale carcasses. Rays, other sharks, tuna, dolphins and sometimes squid and turtles can also be on the menu. The typical diet of an adult white shark centres on seals or sea lions. They usually move on to bigger, higher calorie fare nearer the surface as they grow. Young great whites prey on fishes from the mid-ocean down to the sea floor. White sharks enjoy a varied marine diet, but they are essentially carnivores.
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