While they look similar to the untrained eye, crocodiles and alligators do have distinct differences. These two types of reptiles are found in different parts of the world, and have unique physical distinctions, including different shaped snouts. Both are part of the Crocodilia order, along with caimans and gharials, which also share a superficial resemblance.
Snout Differences
In terms of physical differences, observing the snout — the mouth and nose — is one of the simplest ways to distinguish between a crocodile and an alligator. Crocodiles have long, narrow, V-shaped snouts, while those of alligators are wider and U-shaped. These differences are indicative of the type of diet that each species favors. The wide snout of the alligator packs more crushing power, making it easier to secure prey such as turtles. By contrast, the narrow snout of the crocodile is suited for fish as well as small mammals.
Jaw Differences
The jaws found on a typical crocodile and an alligator are also different. The upper and lower jaws of the crocodile are essentially the same width, with the teeth exposed in an interlocking pattern. They also have a large, protruding fourth tooth on the lower jaw that is accommodated by depressions in the upper jaw just behind the nostrils. The alligator, however, has a wider upper jaw, allowing the lower teeth to fit into it snugly, effectively hiding them from view. Only the teeth of the upper jaw are exposed along the lower jaw line.
Color Differences
Alligators and crocodiles are also slightly different colors. The typical crocodile tends to have a coloration that is an olive brown hue. Alligators usually have a darker, almost black appearance.
Location and Habitat
Crocodiles and alligators are also found in different locations around the globe. Both crocodiles and alligators do well in environments that feature slow moving rivers with grasslands located adjacent to the river banks. Crocodiles live in parts of North, Central, and South America, and can be found in areas of Africa, Australia, and the southeast part of Asia. Alligators are native in the eastern section of China and the southern area of the United States, and are most common in states along the Gulf Coast. The lingual salt glands in crocodiles allows them to be more at home in salt water than alligators.
Branches of the Family Tree
In some circles, it is considered proper to refer to these families as being different branches of a common tree. There are 23 different species in the Crocodilia order found in the world today, and each is in one of three families. The Crocodylidae family includes all the species of crocodiles. The Alligatoridae family includes two subfamilies: Alligatorinae, or alligators, and Caimaninae, or caimans. Caimans resemble alligators and crocodiles, although most species are much smaller. The third family, Gavialidae, includes only one species: the gharial.
Caimans and Gharials
Similar in appearance to other members of the same order, both caimans and gharials are long, semi-aquatic reptiles with extended snouts. Caimans are in the same family as alligators, but most species are much smaller — often around 6.5 to 8 feet (2 to 2.5 meters) long compared to 13 feet (4 meters) for American alligators. These reptiles are found in Central and South America. The gharial, found only in India, has a much narrower snout than other species in this order.
Safety
Both crocodiles and alligators possess a great deal of strength and speed, and even on land, these reptiles are able to pursue and overtake prey with relative ease. People who have not been trained to deal with these animals should not make direct contact. In the event that a crocodile or an alligator has escaped from a zoo or wildlife sanctuary, or wandered from the wild into a populated area, anyone who sees it should leave the immediate area and report the sighting to the authorities.