An alligator has roughly 80 teeth in its mouth at one time. As the teeth wear down, they are replaced with new teeth. An average alligator can go through 2,000 to 3,000 teeth in a lifetime.

The two extant species are the American alligator (A. mississippiensis) and the Chinese alligator (A. sinensis). Additionally, several extinct species of alligator are known from fossil remains.

Alligators first appeared during the Oligocene epoch about 37 million years ago.

Alligators can remain submerged for more than two hours without coming up for air. During this time, their heart rate can drop to 2 or 3 beats per minute to help reduce oxygen consumption.

A group of alligators is called a congregation. A group of newly hatched alligators, or juveniles, is referred to as a pod.

Alligators aren't strict carnivores. They eat fruits and vegetables on occasion and might be important seed-dispersers. They are also surprisingly accomplished climbers, sometimes hauling themselves up trees to get a better basking spot. Oh, and they can use tools. American alligators have been observed using lures to hunt birds, balancing sticks and branches on their heads to attract birds looking for nesting material.

At temperatures above 93 °F or 34 °C, an alligator egg will be born as a male. When the temperature stays below 86 °F or 30 °C, it will be born female. If it stays in the range in between, it could go either way.

Alligators hunt predominantly at night and have been observed using complex social organization during hunts, with large alligators scaring prey towards smaller ones waiting in ambush, or working in teams to trap schools of fish in circles, then feeding in shifts.

Alligators can swim up to 20 mph (32.18 km/h) and run on land as fast as 11 mph (17.7 km/h).

Don't panic if you see an alligator with its mouth open. Most people assume this is a sign of aggression, but this behavior, known as "gaping", is simply a way to cool off. Alligators don't sweat, so they lie with their mouth open to release heat.