Despite being entirely different animals (sharing the order Crocodilia, but not a family), people often wonder about the difference between crocodiles and alligators. After all, they appear to be very similar. To the untrained eye, both look like prehistoric swamp lizards, but there are some tricks you can use so you don’t make a faux pas the next time you’re in Florida. 

The quickest way to tell the two reptiles apart is by their smile: In both animals' lower jaws, they have a long tooth on either side. When crocodiles close their mouths, you can see these long teeth protrude from their faces. Alligators, on the other hand, slip them into sockets in their upper jaw. As a general rule, the toothier the crocodillian, the more likely it is a crocodile.  

Crocodile snout, iStock

Other things to look for include head shape and skin color. Crocodiles tend to have V-shaped faces, while alligators sport shorter, U-shaped snouts. Gators also have darker, greener skin than their tannish brown counterparts. 

In terms of geography, crocodiles are much more common, inhabiting a good chunk of the eastern hemisphere and Central America. Alligators are more modest in their population, living mostly in South America and the southern United States, with a tiny pocket in China. 

There are 23 species of crocodilians, so there is a lot of variation to consider. When trying to identify your giant reptile, the tooth rule is key. Like sharks, crocodiles and alligators can regrow their missing teeth, so the pointy indicators are very likely to always be there.

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