This week's big movie release, "Piranha 3D," does for the toothy South American fish what "Jaws" did for sharks 35 years ago. Hordes of mega-piranhas terrorize bikini-clad beauties ... in 3-D. If that doesn't sound like summer box-office bait, I don't know what does. But are piranhas anywhere close to being as badass as the movie makes them out to be? Ichthyologists say no.

"There's no proof a piranha has ever killed and eaten a human being," Ashleigh Clews, an aquarist at the National Aquarium in Washington, tells Discovery News' Jorge Ribas in a video reality check. "In fact, quite the opposite: Humans are piranhas' biggest predator."

To be sure, the real-life fish look scary: They have mouthfuls of teeth that can close together like interlocking razors, and when they're hungry, swarms of piranhas can quickly strip a dead duck down to the bone. But if you don't bother them, they won't bother you. In fact, they're considered "relatively nervous and skittish."

The piranhas' fearsome reputation arises mostly from descriptions of their frantic meat-eating frenzies, such as President Theodore Roosevelt's awestruck account in his 1914 book "Through the Brazilian Wilderness." Their willingness to scavenge human corpses in the Amazon has also been well-documented. But going after swimmers in an Arizona lake? That's a case of Hollywood overkill.

Click these links for more on piranha facts vs. fiction:

• Toothy 3-foot-long piranha fossil found
• Ten of the scariest animals in nature
• The best worst animal attack movies ever
• Cosmos magazine: Study says man-eating piranhas are a myth
• L.A. Times: Lake Havasu fears 'Piranha 3D' could take a bite out of tourism
• Driver cited in Lake Havasu City for transporting piranhas, gators (2002)

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