14 Amazing Facts About Alligators

Bellowing alligator

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Alligators are reptiles and members of the crocodilian family, which includes crocodiles, caimans, American alligators, and Chinese alligators. These cold-blooded reptiles usually grow from 6-11 feet long and live mainly in wetland areas. American alligators can be found in the wild in Louisiana and Florida, where they were once nearly extinct. Today, they are off the endangered list and thriving in bayous, lakes, and even on golf courses.

These mostly meat-eating reptiles fascinate many people with their strength, speed, and ferocity — but there's even more to alligators than meets the eye. From glow-in-the-dark eyes to amazingly loud roars, discover the most wild alligator facts.

1. Alligators Are Ancient.

Ancient crocodile fossil
Ancient crocodile fossil.

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Alligators, along with other crocodilians, have gone through very little evolutionary change since the time of the dinosaurs. American alligators appeared about 84 million years ago, while their ancestors evolved more than 200 million years ago. The only older reptiles are turtles and tortoises. In fact, alligators are more closely related to dinosaurs than to other modern reptiles.

2. They Can't Survive in Salt Water.

Swimming alligator in grassy swamp area

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Unlike crocodiles, alligators don't have the ability to eliminate salt from their water, so they can't swim in salt-water habitats like mangrove swamps. So if you see a crocodilian in saltwater, you can bet it's not an alligator.

3. The Largest Alligator Weighed Over a Thousand Pounds.

Huge alligator on a log in a river

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The biggest alligator in the world (so far) was 15 feet 9 inches long and weighed in at 1,011.5 pounds. This gator was caught in Mill Creek, a tributary of a river in Alabama. Some crocodiles are even larger than that; the largest crocodile in captivity is Cassius, an Australian croc who is 17 feet long.  

4. The Sex of an Alligator Is Determined by Temperature.

Alligator eggs hatching

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That's right — if the temperature in the baby alligator nest is warm, male alligators are born; if the temperature is cool, the babies are females. Mother alligators lay their eggs on a mound of dirt. When the eggs are ready to hatch, the baby alligators use an "egg tooth" on top of their snouts to break the eggshell.

5. They Can Run Fast, but Tire Quickly.

Alligator running

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Alligators are built for speed, not endurance. They can run up to 35 miles an hour — faster than most humans — but they are sprinters and can't keep up that pace for long. In the water, they can lunge at up to 30 miles per hour. They can also swim very fast by using their powerful tails to propel them forward.

6. Alligator Eyes Glow in the Dark.

Glowing alligator eyes in a river at night
Glowing alligator eyes in a river at night.

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Alligators' eyes are on the top of their heads, making it easy for them to lie almost entirely submerged and still see their prey. Alligators, like cats, also have a structure in the back of their eyes that reflects light to improve night vision. If you catch an alligator's eyes with a flashlight, they will glow red. You can also tell how big an alligator is by the distance between its eyes: the greater the distance, the longer the alligator.

7. While They Prefer Meat, They Aren't Opposed to Fruit.

Alligator eating a crab

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Alligators are considered carnivores but have been known to eat fruit. Younger alligators eat bugs, amphibians, and small fish, while their parents snack on larger fish, snakes, turtles, birds, and mammals.

8. They Thrive in Slow-Moving Waters.

Chinese alligator

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All alligators live in freshwater; they usually prefer slow-moving rivers, creeks, marshes, swamps, and lakes. American alligators live in slow waters in the southeastern part of the United States, from North Carolina to Texas. The Chinese alligator, a close relative, lives almost exclusively in the lower Yangtze River in China.

9. Alligators Can Go Through 3,000 Teeth in Their Lives.

American alligator showing its teeth

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Alligators have about 75 teeth in their mouth at any one time, but as the teeth wear down or break off they are replaced. As a result, many can have about 3,000 teeth over the course of their lives. According to some sources, alligators can bite with a force of nearly 3,000 pounds per inch, making their bite among the most powerful in the world.

10. Unlike Most Reptiles, They Care for Their Young.

Mother alligator with babies on her back

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For about two years, female reptiles carry and look after their babies, making sure they are safe and well-fed. Babies grow about a foot per year, so they are good-sized predators by the time they head off on their own.

11. Alligators Spend Months in Gator Holes.

Alligators don't hibernate, but they do go through a dormancy period during colder weather. Before going dormant, they dig out a "gator hole," which is a depression or tunnel in the mud. Gator holes can be up to 65 feet long, and they protect the alligators when it's too hot or cold for comfort.

12. They Are the Loudest Reptiles in the World.

Alligator bellowing

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Both males and females emit loud roars when they're mating that make alligators the loudest reptiles in the world. Males also roar to attract mates and scare off potential predators.

13. Alligators May Eat Their Young.

Baby alligators with adult

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Researchers noted that a large number of baby alligators seem to die off before maturity, and they investigated the cause. They discovered that baby alligator mortality is due, in part, to the fact that about 7% of them are eaten by their parents.

14. Alligator Blood Is Antibiotic and Antiviral.

A study found that wild alligator blood has both antibiotic and antiviral properties. In fact, it is active against HIV-1, West Nile Virus, and Herpes simplex virus. These properties also help protect the alligators themselves from infection after injury.

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