Can piranhas really strip a cow to the bone in under a minute?

Ever since Teddy Roosevelt witnessed a piranha feeding frenzy in the Amazon, the small fish have been known as fearsome predators. But can they really strip a cow to the bone?

Hollywood picked it up from there with the 1978 horror flick "Piranha" ("When flesh-eating piranhas are accidentally released into a summer resort's rivers, the guests become their next meal"), 1981's "Piranha II: The… » Full Story on HowStuffWorks