I thought this was important for you to know before your child asks you or his/her teacher. I was embarrassed when I was asked this at a class I attended with my 18 year old.
The first difference between a crocodile and an alligator is that they are from different families of crocodilians. Crocodiles are from the crocodylidae family, while alligators and caiman are from the alligatoridae family.
In terms of physical differences the easiest way to tell the difference between the two is that a crocodile has a very long, narrow, V-shaped snout, while the alligator’s snout is wider and U-shaped. Because of the wide snout of the alligator it packs more crushing power to eat prey like turtles that constitute part of its diet. The narrow crocodilespan> snout, although still very powerful, is not really suited for prey like turtles but is very versatile for fish and mammals.
Another physical difference between the crocodile and the alligator is that the crocodile’s upper and lower jaws are nearly the same width, so the teeth are exposed all along the jaw line in an interlocking pattern, even when the mouth is closed. They also have an enormous 4th tooth on the lower jaw that is accommodated by depressions in the upper jaw just behind the nostrils.
An alligator, on the other hand, has a wider upper jaw, so when its mouth is closed the teeth in the lower jaw fit into sockets of the upper jaw, hidden from view. Only the teeth of the upper jaw are exposed along the lower jaw line. Even the enormous 4th tooth on the bottom jaw, which is exposed in a crocodile, is hidden in the alligator.
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