Both alligators and crocodiles are crocodilians, an ancient branch of reptiles that’s more closely related to birds and dinosaurs than to many modern lizards- in fact, they’re birds’ closest living relatives. But while it’s pretty easy to tell a bird from a croc (we hope), what’s the difference between an alligator and a crocodile?

There are a few rules of thumb you can use to tell these animals apart. Generally speaking, crocodiles have skinnier snouts than alligators, and they’re usually lighter in color. Crocodiles are typically bigger than alligators, too- on average, alligators are about 13 feet long, but saltwater crocodiles, at lengths of over 20.7 feet, are the largest land-dwelling predators in the world. It’s not a perfect way of telling them apart, though- the African dwarf crocodile is only about 4 feet long, far smaller than a gator. But there is one foolproof way of telling them apart- their teeth. Alligators’ upper jaws are wider than their lower jaws, so when their mouths are closed, you can’t see their bottom teeth. Crocs, on the other hand, have upper and lower jaws that are about the same width, so when their mouths are closed, you can see their lower teeth. But you probably wouldn’t want to be close enough to a croc or a gator to be able to tell details like thatNile_crocodile_head.jpg– they’re amazing animals, but they definitely need their space!


Photo by Leigh Bedford