Forty years later, we're still in the grip of "Jaws." We quiver at the thought of a shark. Even if we never saw the movie, even if we weren't old enough to see the sensation it created, it has helped stoke our fear of -- and fascination with -- these great predators of the ocean.
How dangerous are they really? Many marine biologists will say they just don't go after human beings very much -- that we hear about shark attacks because they are rare and fearsome. In 2010, there were 32 confirmed shark attacks in North American waters, says National Geographic. Your chances of dying of the flu are 1 in 63; your chances of being killed by a shark are 1 in 11 million.
But we're still scared. So National Geographic's Nat Geo WILD channel is running a nine-hour "Sharkathon" Friday, partly so we can revel in fear from the safety of our TV sets, partly to set the record straight.
The evening will culminate in a program called "Shark Attack Experiment Live." During the program, scantily-clad swimmers will dive in shark-infested waters off the cost of South Africa to show whether sharks really care about bare human skin.
"This is no stunt," say the producers; "the goal is to dispel negative myths about sharks and raise public awareness that some shark species are being driven to extinction by overfishing."
For every human being killed by a shark, says Nat Geo WILD, humans kill approximately two million sharks.
Still, the beasts are something to see. Great white sharks, the largest, can weigh 5,000 lbs and average 15 feet in length. Different species have thousands of jagged teeth.
"National Geographic has produced many dozens of films where expert cameramen and scientists researched and filmed sharks while diving among them in open waters," said Geoff Daniels, senior vice president for Nat Geo WILD. "Typically viewers see the end product of those dives, but this live broadcast allows them to share in the immediacy of the experience."
The programming marathon begins at noon ET and runs until 9 p.m. You can digest a lot of turkey while it's on.