Can Piranhas Smile?

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Piranhas have a reputation for being some of the more ferocious fish in the world. If you take one look at their spiky, razor-sharp teeth, you might just believe that myth. As it turns out, piranhas could be some of the most misunderstood fish in the world, too.

Yes, they do attack humans from time to time, although the result usually isn’t fatal. Some of the more than 20 species of piranhas are even vegetarian; just one, the red-bellied piranha, tends to sometimes set its sights on human flesh. This only happens when they're extremely hungry and can't find other fish and animals to dine on. Like their feeding habits, whether or not these mysterious fish smile is also a topic for debate.