ALL crocodilians have transparent third eyelids located at the front corner of the eyes which cover them for protection when swimming underwater, but allows the crocodilian limited vision to see where it is going. Crocodilians shed their teeth periodically, and the closing pressure of an adult s jaws is greater than 1000 lbs. They also have a voice, which is used for mating, warning, and other social communication. All are nocturnal hunters with extremely good vision. They have a vertical slit pupil which permits more light to enter the eye and register on the retina than would be possible with a round pupil.
Crocodilians also have reflective layer called a tapetum lucidum which is similar to cats and dogs.
The most noticeable difference among crocodilians is the shape of their snouts. Caimans such as Samuel Adams are in the subfamily Alligatorinae . Well, caimans rank among the smallest of all crocodilians. Also, their heads closely resemble those of alligators, but they are not quite as broad. For instance, they stretch their necks out of water, arch their backs, and thrust almost vertically to swallow their food.