It may look like a slightly cuddlier version of the crocodile, but it's just as ferocious. The Cuvier's dwarf caiman is the smallest croc around, usually getting no bigger than about 4 ft. to 4½ ft. (1.2 m to 1.4 m) in length. These guys are found in cool, fast-moving rivers in South America, and sometimes live in waterfalls and rapids. Even with its small size, a dwarf caiman eats birds, fish, other reptiles and even some small mammals. Considered a keystone species because it maintains the ecosystem it lives in by preying on certain fish (which would dramatically change that ecosystem if left unchecked), it has very few predators thanks to its armored, jagged skin.
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