CROCODILIANS, THE PREDATORS FROM THE PAST AND THE FUTURE

Crocodilia is an order of reptiles formed by 3 different families. Those families contain genera such as crocodiles, alligators, caimans, gharials and false gharials. They have a semi-aquatic and predatory lifestyle for which they have developed some amazing adaptations. Most of them are quite big and some are giant creatures, like the saltwater and Nile crocodiles. If you want to learn about the tools that make these animals some of the most amazing predators in the world, I recommend you keep reading.

Photo by: Lip Kee
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Just as any other predator, these reptiles have a diverse arsenal of weapons that they use to hunt. All have brutal bite forces that they use to grasp their preys tightly, leaving their victims with no option to scape. For example, the Nile crocodile, despite being the second biggest crocodile, has the strongest bite in the animal kingdom. With a snap of its jaws, it can create a pressure of 5,000 psi, 4 times the bite of a grizzly bear. But if it was not enough with their amazing bite force, their jaws are full of sharp teeth. Each of those teeth can be replaced up to 80 times in their life if it was necessary.

They are stalk and ambush predators, which means that they slowly approach their preys and then perform fast and brutal attacks. These usually take place by the river banks although, in the case of some species, they hunt far from the edge, where they catch flying birds or leaping fish. Once these predators have caught their prey, they drown it. When the prey is not fighting back anymore, their can cut it up. As crocodilians can not use their hands to grab the prey while pulling with their teeth, they have a cutting technique known as the death roll. They catch the prey with their teeth and roll violently to tear the pieces apart. Sometimes, they organize in groups and they tear the prey apart all together. Each one accepts the piece it is left with and does not fight for a bigger piece.

Photo by: Kumiko
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Even though they are one of the top predators, crocodilians can also get attacked. Therefore, they have developed a few defense mechanisms. Their skin is thick and keratinized, which makes it very tough. Over that skin, they have layers of non-overlapping scales called scutes. The externa surface of these scales is covered in beta-keratin, with is hard. The space between scales is covered in alfa-keratin, which is a little bit softer. These scutes (scales) are sometimes reinforced by bony plates known as osteoderms.

When they feel threatened, crocodilians base their defense on preventive attacks. They try to bite and, when they are attacked from behind, they use their tail. It is muscular and flexible and with it, crocodilians can hit harder than you may think.

Palatal valve is closing the throat.
Photo by: Sunil Soundarapandian
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All these amazing weapons are essential, however, their huge success as predators is mostly supported on their amazing adaptations to aquatic environments. Their tail is flattened to propel them quickly and they can hold their limbs close to the body for better hydrodynamics. To steer, they spread their limbs and use them as flaps. Their buoyancy is controlled by the air volume of their lungs so, if they want to dive deeper, they release air.

To protect some of their organs, they have some interesting features. They have a third transparent eyelid to make sure they can see underwater and do not hurt their eyes. While underwater, their nostrils are shut and their throat is closed by a structure known as palatal valve, which does not let water in their respiratory and digestive systems. When they want to eat, they must do it on land, as the palatal valve needs to open to let food by.

These reptiles have managed to adapt to semi-aquatic life to perfection and thank to that they have become one of the most famous predators in the world. 95 million years of evolution since they first lived in our planet have helped to create one of the most magnificent creatures to ever live. So, the next time you see one, you have some more reasons to admire them at a safe, long distance.