Crocodiles are large aquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term is sometimes used even more loosely to include all extant members of the order Crocodilia, which includes the alligators and caimans. Although they appear to be similar to the untrained eye, crocodiles, alligators and the gharial belong to separate biological families. Many species are at the risk of extinction, some being classified as critically endangered.
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