Piranhas: nature's tiny, toothy PR problem. If your mental image of a South American vacation involves being devoured alive by a school of razor-mouthed fish, you can probably relax - but maybe keep your toes out of the murky water just in case. These freshwater fish are indeed native to South America, but they're not exactly lining up to snack on tourists. They prefer smaller prey like fish, frogs, and bugs, and they even eat plants. A healthy human splashing around is more likely to be ignored or avoided than attacked. That said, piranha bites do happen, and they can be serious. In Brazil, a little girl lost two toes to a piranha at Lago Sul, a popular swimming lake. Near Manaus, eight tourists were bitten near their resort, though most bites were minor - victims didn't even realize they'd been chomped until they got out of the water. So what are the actual risks? Piranhas generally live in freshwater rivers, streams, and muddy areas - not the kind of crystal-clear beaches tourists flock to. You're unlikely to encounter them at Copacabana Beach. But if you do find yourself in piranha territory, avoid swimming where there are warning signs or reports of bites. Shallow, drought-shrunken lakes are especially risky, as hungry fish compete for scarce food. And for heaven's sake, don't try to fish for them - many bites happen when the fish are out of the water. If you see piranhas or feel a nip, move calmly to shore - panicked splashing might make you look like a dying animal, which is exactly the kind of snack they'd consider. Treat any bite like a serious cut: apply pressure, seek medical help, and avoid swimming with open wounds in murky water, where infections can be worse than the bite itself. In short, piranha attacks are rare, not zero, and mostly avoidable with common sense. So go ahead, enjoy that Amazon river cruise - but maybe skip the skinny-dipping.