American alligator
The American alligator (Alligator mississippiensis), sometimes referred to colloquially as a gator or common alligator, is a large crocodilian reptile native to the Southeastern United States and a small section of northeastern Mexico. It is one of the two extant species in the genus Alligator, and is larger than the only other living alligator species, the Chinese alligator.
Not to be confused with the American crocodile.
Adult male American alligators measure 3.4 to 4.6 m (11.2 to 15.1 ft) in length, and can weigh up to 500 kg (1,100 lb), with unverified sizes of up to 5.84 m (19.2 ft) and weights of 1,000 kg (2,200 lb) making it the second largest member by length and the heaviest of the family Alligatoridae, after the black caiman. Females are smaller, measuring 2.6 to 3 m (8.5 to 9.8 ft) in length.[5][6][7][8][9] The American alligator inhabits subtropical and tropical freshwater wetlands, such as marshes and cypress swamps, from southern Texas to North Carolina.[10] It is distinguished from the sympatric American crocodile by its broader snout, with overlapping jaws and darker coloration, and is less tolerant of saltwater but more tolerant of cooler climates than the American crocodile, which is found only in tropical and warm subtropical climates.
American alligators are apex predators and consume fish, amphibians, reptiles, birds, and mammals. Hatchlings feed mostly on invertebrates. They play an important role as ecosystem engineers in wetland ecosystems through the creation of alligator holes, which provide both wet and dry habitats for other organisms. Throughout the year (in particular during the breeding season), American alligators bellow to declare territory, and locate suitable mates.[11] Male American alligators use infrasound to attract females. Eggs are laid in a nest of vegetation, sticks, leaves, and mud in a sheltered spot in or near the water. Young are born with yellow bands around their bodies and are protected by their mother for up to one year.[12] This species displays parental care, which is rare for most reptiles. Mothers protect their eggs during the incubation period, and moves the hatchlings to the water using her mouth.[13]
The conservation status of the American alligator is listed as Least Concern by the International Union for Conservation of Nature. Historically, hunting had decimated their population, and the American alligator was listed as an endangered species by the Endangered Species Act of 1973. Subsequent conservation efforts have allowed their numbers to increase and the species was removed from endangered status in 1987. The species is the official state reptile of three states: Florida, Louisiana, and Mississippi.
Phylogeny[edit]
Members of this superfamily first arose in the late Cretaceous, about 100–65 million years ago (Mya). Leidyosuchus of Alberta is the earliest known fossil, from the Campanian era 83 to 72 Mya. Fossil alligatoroids have been found throughout Eurasia, because bridges across both the North Atlantic and the Bering Strait connected North America to Eurasia about 66 to 23 Mya.
Alligators and caimans split in North America during the late Cretaceous, and the caimans reached South America by the Paleogene, before the closure of the Isthmus of Panama during the Neogene period, from about 23 to 2.58 Mya. The Chinese alligator likely descended from a lineage that crossed the Bering land bridge during the Neogene. Fossils identical to the existing American alligator are found throughout the Pleistocene, from 2.5 million to 11.7 thousand years ago.[17] In 2016, a Late Miocene fossil skull of an alligator dating back to approximately 7-8 Mya was discovered in Marion County, Florida. Unlike the other extinct alligator species of the same genus, the fossil skull was virtually indistinguishable from that of the modern American alligator. This alligator and the American alligator are now considered to be sister taxa, meaning that the A. mississippiensis lineage has existed in North America for 7-8 million years.[1]
The alligator's full mitochondrial genome was sequenced in the 1990s, and it suggests the animal evolved at a rate similar to mammals and greater than birds and most cold-blooded vertebrates.[18] However, the full genome, published in 2014, suggests that the alligator evolved much more slowly than mammals and birds.[19]
Culture and film[edit]
The American alligator is the official state reptile of Florida,[145] Louisiana,[146] and Mississippi.[147] Several organizations and products from Florida have been named after the animal.
"Gators" has been the nickname of the University of Florida's sports teams since 1911. In 1908, a printer made a spur-of-the-moment decision to print an alligator emblem on a shipment of the school's football pennants.[148] The mascot stuck, and was made official in 1911, perhaps because the team captain's nickname was Gator.[149] Allegheny College and San Francisco State University both have Gators as their mascots, as well.[150]
The Gator Bowl is a college football game held in Jacksonville annually since 1946, with Gator Bowl Stadium hosting the event until the 1993 edition. The Gatornationals is a NHRA drag race held at the Gainesville Raceway in Gainesville since 1970.