Crocodiles are very fast swimmers, which helps them catch their prey.

It is so good, in fact, that they can hear their babies calling from inside their eggs.

In addition to their strong jaws, crocodiles have very keen hearing.

The crocodile jaw has very little opening strength, though a crocodile's mouth can be held shut with just a rubber band. For comparison, a human jaw produces only about 100 pounds of pressure per square inch. This means that they can bite through a human arm or a leg with no problem.

A crocodile's jaws can apply 3,700 pounds of pressure per square inch, according to National Geographic.Crocodile tears aren't usually noticeable unless the croc has been out of the water for a while and the eyes begin to dry out. The fluid helps clean the eye, lubricate it and reduce bacteria. Their lacrimal glands secrete a fluid behind their third eyelid, called a nictitating membrane. However, crocodiles do in fact produce tears, according to the Crocodilian Biology Database. It is a saying that goes back to about the 16th century. 'Crying crocodile tears' refers to a person expressing insincere remorse.To keep cool, they open their mouths in a process called 'mouth gaping,' which is a lot like panting. These reptiles can go through 8,000 teeth over a lifetime, according to the San Diego Zoo. When a crocodile loses a tooth, it is quickly replaced.Do you see any tears yet? (Image credit: Getty) crocodilesĪ close-up of a crocodile's eye. The American crocodile is considered vulnerable by the IUCN, but its population is increasing. Poaching is a constant threat to the species. It is considered critically endangered and has a population of only about 4,000, according to the International Union for Conservation of Nature (IUCN). The Cuban crocodile is one of the world's most endangered species of crocodile. How long a crocodile lives depends on its species some, such as the Dwarf crocodile, live to around 40 years, while others, such as the Nile crocodile, live up to 80 years, according to Animalia. The sex of each crocodile baby depends on the temperature of its egg during a critical moment during the first half of its incubation period.Ĭrocodile babies measure about 7 to 10 inches (18 to 25 centimeters) long when they are born and don't mature until they are 4 to 15 years old. The hatchlings stay in their eggs for 55 to 100 days. (Image credit: Getty)Ĭrocodiles lay an average of 12 to 48 eggs at a time.

A baby crocodile hatches from its egg in Indonesia.

Crocodile or alligator growl