Piranhas tend to have a fearsome reputation as vicious carnivores who will attack any animal that gets close to them, no matter how large. However, while they can be fearsome predators, piranhas are relatively cautious and will usually only attack larger animals if the creature is obviously dead or dying. The typical diet for a piranha is composed of small creatures, like insects or fish, as well as seeds and other plant material. In fact, some species are completely vegetarian.
Piranhas are attracted to blood and to agitated water, and scientists believe that most cases of piranha attacks occur when food happens to be spilled in water when people are swimming and splashing around.
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