Popularised by Steven Spielberg’s ‘Jaws’ thriller, the great white is a species of large mackerel shark renowned for its daunting size, with some growing up to 20 feet in length – but most are much smaller, with females averaging around 15 to 16 feet and males between 11 and 13 feet. In the Hollywood thriller, the sea creatures were depicted as ferocious man-eaters, but humans are not their preferred prey, in spite of a large number of reported attacks. The earliest known fossils of the great white shark are about 16 million years old, meaning they date back to the mid-Miocene epoch, and researchers argue its origins could be linked to the fall of the Megalodon some four million years ago.
Since then, they have changed massively, adapting to their environment to stay at the top of the ocean’s food chain, Amazon Prime’s ‘Rise of the great white’ documentary revealed.
Narrator Alan Sklar said: “Sharks predate dinosaurs by several hundred million years.
“Their success is due to their ability to adapt to conditions in nearly every nook and cranny of the world’s oceans.
“It’s also based on several major anatomical innovations.
“With torpedo-shaped bodies, powered by tail fins with long upper and lower lobes, sharks are built for speed.
“Great whites move effortlessly through the water, thanks to tooth-like features called denticles that line their skin.”
First studied in the Eighties, this major discovery has since inspired a huge range of innovative creations by humans, from Olympic swimmer’s suits to plane designs.
But that’s not all that helps the great white.
Mr Sklar added: “At just a tenth of a millimetre long, these ridge-lined structures reduce drag by dissipating tiny eddies that form along the skin.
Packed tightly together, rows of denticles help seal out parasites, while forming a concrete-hard seal against strikes from other sharks.
“The shark’s swimming motion is stabilised by a series of large fins along its sides, top and bottom.
“With skeletons made of cartilage, rather than bone, they have the flexibility to accelerate and change directions quickly.
“Predatory sharks seize their prey by lunging and extending their jaws out from their skull.”
The series went on to reveal some of the great white’s favourite spots to hunt for prey.
Published at Wed, 26 Aug 2020 09:50:00 +0000