Alligators are known as living fossils because they have existed for roughly 200 million years, according to LiveScience. American alligators are heavily concentrated in the southeastern states, such as Florida and Mississippi, while the critically endangered Chinese alligator is found in China's Yangtze River basin.
American alligators have thick, scaly skin and armored backs with bony protrusions, known as osteoderms. An alligator's rounded snout is wider than the thin, tapered shape of a crocodile's nose and mouth. Since the alligator's eyes and snout are on the top of its head, it can breathe and scan for prey while hiding the rest of its body underwater, Wildscreen Arkive states. Alligators frequently feed on fish, turtles, insects, snakes and crustaceans, but they also help these creatures survive. American alligators dig holes to stockpile water, which many of their prey rely on during dry periods.
Chinese alligators are smaller than their American counterparts, but they are highly skilled at cracking open clams and animal shells using their blunt teeth, according to LiveScience. Approximately 150 of these species live in the wild, while conservation efforts have boosted the captive population to about 10,000.
Before alligators grow into fierce adults, young hatchlings are prey to raccoons, otters, birds, snakes and other alligators. Females release up to 50 eggs and store them in warm nests. The temperature of the nest affects the sex of an alligator's embryos, LiveScience states. An incubation range of 86 to 93 degrees Fahrenheit could produce either sex; temperatures below 86 F produce females, and temperatures above 93 F produce males.