alligator

Alligators, pictured in the Everglades, Florida, USA. The Everglades is a swampy area at the southern end of the state, and was made a national park in 1947. The alligator is related to the crocodile, but is smaller and less likely to attack people.

Reptile of the genus Alligator, related to the crocodile. There are only two living species: A. mississipiensis, the Mississippi alligator of the southern states of the USA, and A. sinensis from the swamps of the lower Chang Jiang River in China. The former grows to about 4 m/12 ft, but the latter only to 1.5 m/5 ft. Alligators lay their eggs in waterside nests of mud and vegetation and are good mothers. They swim well with lashing movements of the tail and feed on fish and mammals but seldom attack people.

Alligator skin is of value for fancy leather, and according to estimates released in December 2001, there are fewer than 130 Chinese alligators remaining in the wild. Numbers have been decreasing by 4–6% a year and alligator farms have been established in the USA.

Closely related are the caymans of South America; these belong to the genus Caiman. Alligators ranged across northern Europe from the Upper Cretaceous to the Pliocene period.

Alligators differ from caymans by having a bony septum between the nostrils; they differ from crocodiles by having a broad head, depressed and obtuse muzzle, and unequal teeth, the fourth from the front on each side of the lower jaw being elongated and fitting into a cavity in the upper jaw when the mouth is closed.