Thousands of fish species — about 2,500 of them named — call the Amazon River home, but scientists estimate nearly half of the marine creatures lurking in the massive stretch of water remain ...

Learn more about piranhas, why they have such a powerful bite, and why there are so many misconceptions around them.

(CNN) — A toothy toadstool. A vegetarian piranha with a distinctive mark. And a pygmy pipehorse floating in the Indian Ocean shallows. These wild wonders were among the hundreds of previously unknown ...

It goes without saying that you could find some pretty dangerous animals if you were to travel back in time tens of millions of years ago, but not all of the creatures that lurked in prehistoric times ...

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