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It may be hard to fathom, but many great white encounters with humans are investigative, not predatory. (A great white attacks a seal decoy in False Bay.) They’re just curious, Compagno says. (Brandon Cole)

Forget Jaws, Now it's . . . Brains!

Great white sharks are typecast, say experts. The creatures are socially sophisticated and, yes, smart

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In the murky predawn light, our speedboat hurdles across Cape Town, South Africa's False Bay. A fierce wind whips the seas, pitching our 26-foot craft and sending an eerie scream across the white-tipped waves. We are hoping to come face to face with one of the earth's most feared predators: the great white shark. Alison Kock, a marine biologist, has made this journey more than 500 times since 1999, striving to unlock the shark's many mysteries.

We approach a flat, rocky island a quarter-mile long and crowded with about 60,000 Cape fur seals. "They want to go to sea to feed, but they're afraid of the white sharks," Kock says. The hungry seals dive into the water in a desperate swim for their feeding grounds 40 miles out in the bay. They must run a gantlet of great whites waiting for them just off Seal Island.

The attacks begin a few minutes later. A 3,000-pound great white explodes out of the water. In midair the shark lunges at a seal and flips back into the water with a mighty splash. Moments later another shark breaches and bites a seal. We speed to the spot, in time to see a pool of blood. Scores of gulls hover above, screeching in excitement, then swoop down to gobble up any leftovers.

During an hour and a half, we witness ten great white sharks hurtling out of the water to grab seals. As the rising sun brightens the sky, the attacks stop.

"That's it for today," Kock says. "The great whites only attack in the hour after dawn. We think it's because once there's enough sunlight, the seal can see the shark coming at it from below and escape."

Despite this awesome display of predator power, Kock and other researchers claim that the shark has been defamed: its reputation as a ruthless, mindless man-eater is undeserved. In the past decade, Kock and other shark experts have come to realize that sharks rarely hunt humans—and that the beasts are sociable and curious. Unlike most fish," Kock says, "white sharks are intelligent, highly inquisitive creatures."

Perhaps the largest great white shark ever caught was off Malta, in the Mediterranean Sea, in 1987. It was reported to be 23 feet long and weigh 5,000 pounds. (Many scientists are skeptical and put the maximum length for a great white at closer to 21 feet.) A sea turtle, a blue shark and a dolphin, and a bag full of garbage were found in the giant's innards.

The great white shark is a top predator throughout the world's temperate and subtropical waters. It's found most commonly off South Africa, New Zealand, Australia and the United States, where most sightings occur in the waters off California and the mid-Atlantic coast. With its torpedo shape and heavily muscled tail, a great white can swim 15 miles per hour or faster when attacking. It has about 240 serrated teeth in up to five rows.

No one has seen great white sharks mate. Males are distinguished by a pair of sperm-delivery organs called claspers that extend from the pelvic fins. After mating, eggs hatch inside the female's uterus. Gestation takes at least a year, then 2 to 12 babies are born. In some shark species, the strongest fetuses eat their weaker brothers and sisters in the womb; no one knows whether great whites do so.

Sailors have feared great white sharks for centuries. In 1862, Jonathan Couch wrote in his History of the Fishes of the British Isles that in the West Indies, the great white "is the dread of sailors who are in constant fear of becoming its prey when they bathe or fall into the sea." In 1812 the British zoologist Thomas Pennant wrote that "in the belly of one was found a human corpse entire, which is far from incredible considering their vast greediness after human flesh."

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