A Crocodile is a large reptile found in tropical regions of Africa, Asia, the Americas, and Australia. They are members of the order Crocodilia, which also includes caimans, gharials, and alligators.
There are 13 species of crocodiles, so there are many different sizes of the crocodile. The smallest crocodile is the dwarf crocodile. It grows to about 5.6 feet (1.7 meters) in length and weighs 13 to 15 pounds (6 to 7 kilograms).
The largest crocodile is the saltwater crocodile. The largest one ever found was 20.24 feet (6.17 m) long. They can weigh up to 2,000 pounds (907 kg). Crocodiles lay 10 to 60 eggs at a time. The hatchlings stay in their eggs for 55 to 110 days.
They are 7 to 10 inches (17.8 to 25.4 centimeters) long when they are born and don’t mature until they are 4 to 15 years. How long a crocodile life depends on its species. Some only live to around 30 years, while others live up to 75 years.
During their 215-million-year evolutionary history, beginning in the middle Triassic, these magnificent beasts invaded diverse habitats. In that case, from ocean to swamp, from wet tropical forest to cascading mountain rivers.
Today’s comparatively small remnant of this once diverse group still lives in these areas. But, their numbers grow smaller with poaching and the continuing, unstoppable destruction of their habitat by world overpopulation.
What are the Crocodilians?
The Class Crocodylia consists of twenty-two species of alligators, caimans, gharials, and crocodiles worldwide, and is most closely related to birds (class Aves). Like birds (and mammals), Crocodilians have the ventricle of their heart divided into left and right compartments.
Unlike amphibians, turtles, and reptiles, whose ventricles have but a single, undivided compartment. In addition, like mammals and birds, crocodilians demonstrate much parental care of their young. Eventually, a behavior not found in amphibians, turtles, reptiles, and tuataras.
Crocodilians are covered with scales, a trait they share with reptiles (and to some extent with turtles. But, not with amphibians, (whose skin is scaleless and permeable). And their cloacal opening is a longitudinal slit (not transverse as in the classes Reptilia and Rhynchocephalia).
Always remember, Crocodilians are no longer classified as reptiles but are considered a distinct and unique evolutionary lineage, the class Crocodylia. Also, Crocodilians are tropical and subtropical in distribution. Some species, such as the saltwater crocodile, can attain lengths of up to 7 meters (23 feet).
READ MORE: About the Saltwater Crocodiles
Their General Classification Outlook
Reaching lengths of more than 23 feet (6.5 m) and weighs over 2,200 pounds (~1,000 kilos), the saltwater crocodiles are the largest reptile on the planet. Not to mention, they are formidable predators throughout their range.
Again, Saltwater crocodiles of this size are capable of eating just about any animal that strays too close. And are particularly adept at drowning terrestrial creatures like birds and mammals. Named for their ability to survive in full salinity seawater. In reality, saltwater crocodiles typically live in brackish (low salinity) water near the coast.
- Kingdom: Animalia
- Phylum: Chordata
- Class: Reptilia
- Order: Crocodylia
- Family: Crocodylidae
- Genera: Crocodylus, Mecistops and Osteolaemus
- Species: 13, including C. porosus (saltwater crocodile), C. acutus (American crocodile), C. niloticus (Nile crocodile), C. rhombifer (Cuban crocodile), M. cataphractus (African slender-snouted crocodile), O. tetraspis (African dwarf crocodile)
The Cuban crocodile is one of the world’s most endangered species of crocodile. It is considered critically endangered and has a population of only about 4,000. Poaching is a constant threat to the crocodile species.
The American crocodile is also considered vulnerable by the International Union for Conservation of Nature and Natural Resources, but their populations are increasing. Some species, such as the saltwater crocodile, can attain lengths of up to 7 meters (23 feet).
How are Alligators and Crocodiles different?
Crocodiles are often confused with alligators, but there are some easy-to-spot differences. An alligator’s jaw is U-shaped, while a crocodile has a V-shaped jaw, according to the San Diego Zoo. Crocodiles also have teeth that stick up over their upper lip when their mouths are closed.
Another difference between alligators and crocodiles is that crocs have salt glands on their tongues. These modified salivary glands help crocs tolerate living in saltwater. Alligators and caimans have lost the ability to secrete excess salt through the tongue glands and therefore, they prefer to live in freshwater areas.
When a crocodile loses a tooth, it is quickly replaced. These reptiles can go through 8,000 teeth over a lifetime. Crocodiles don’t sweat. To keep cool, they open their mouths in a process that is called “mouth gaping,” which is a lot like panting.
Where does a Crocodile live?
Coming face to face with a crocodile or an alligator, you’d see a mouth full of serrated teeth that would likely scare the bejeezus out of you. As can be seen, from the previous description, the two reptile groups are close relatives, so their physical similarities are expected.
During the Mesozoic Era, about 100 million years ago, the Crocodilia order was one of the top animals on the food chain. Today, crocodiles are found in the tropical habitats of Africa, Asia, Australia, and the Americas. They normally live near lakes, rivers, wetlands and even some saltwater regions.
One of the largest known populations of American crocodiles is found in the Dominican Republic’s at a large saltwater lake called Lago Enriquillo, according to National Geographic.
Crocodiles live in tropical climates for a reason. They are cold-blooded and cannot generate their own heat. During colder months, they hibernate or go dormant. Crocodiles will also go dormant during long periods of drought. To create a place to hibernate, they dig out a burrow in the side of the riverbank or lake and settle in for a long sleep.
What does a Crocodile eat?
Crocodiles are carnivores, which means they eat only meat. In the wild, they feast on fish, birds, frogs, and crustaceans. At the zoo, they eat small animals that have already been killed for them, such as rats, fish or mice. They also eat live locusts.
In the wild, crocodiles will clamp down on their prey with their massive jaws, crush it, and then they will swallow the prey whole. They do not have the capability to chew or break off small pieces of food like other animals.
To help with digestion, crocodiles swallow small stones that grind up the food in their stomachs. Thanks to their slow metabolisms, crocodiles can survive for months without food.
Crocodiles are very fast swimmers, which helps them catch their prey. They can swim up to 20 mph (32 kph) and can hold their breath underwater for around one hour. On land, crocodiles aren’t nearly as fast. They can only run up to 11 mph (17.6 kph) for a short distance.
READ MORE: Crocodiles Food Chain Facts You Should Know
A crocodile’s jaws can apply 5,000 pounds of pressure per square inch. This means that they can bite through an arm or a leg with no problem. A human’s jaw only produces 100 pounds of pressure per square inch. The crocodile jaw has very little opening strength, though. For example, a crocodile’s mouth can be held shut with a rubber band.
In addition to their strong jaws, crocodiles also have very keen hearing. It is so good, they can hear their babies calling from inside their egg.
“Crying crocodile tears” refers to a person expressing insincere remorse. It is a saying that goes back to about the 16th century. Crocodiles DO produce tears. Their lachrymal glands secrete a fluid behind their third eyelid, called a nictitating membrane.
The fluid helps clean the eye, lubricate it and reduce bacteria. 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. It is illegal to hunt crocodiles for their skin. This makes their skin very rare. A purse made from crocodile skin can cost more than $10,000.
I hope you loved reading, learning and understanding more about The Crocodilia Evolution. However, if you’ll have more additions, contributions, suggestions or even questions, please let us know how we could help. Therefore, Contact Us or even leave your queries in the comments box below this post.
You must log in to post a comment.