Crocodile are the worlds largest and perhaps most exciting reptiles. They are also great survivors and their prehistoric ancestors, the Archosaurs, date back over 240 million years to the Triassic period. They have survived major upheavals such as the break up of the continents and the ice ages. They have witnessed the rise and fall of the dinosaurs and have seen the evolution of mammals and birds. Since man colonised the world, no species of crocodile has become extinct; however 17 out of the 23 species of crocodilians around the world are endangered.
Crocodiles are very fast over short distances, even out of water. They have extremely powerful jaws and razor-sharp teeth for tearing flesh, but cannot open their mouth if it is held closed, hence there are stories of people escaping from the long-snouted Nile Crocodile by holding its jaws shut. All large crocodiles also have sharp and powerful claws. Crocodiles are ambush hunters, waiting for fish or land animals to come close, then attacking with a rush. As cold-blooded predators, they can survive long periods without food, and rarely need to actively go hunting. Despite their slow appearance, crocodiles are top-level predators in their chosen environment, and various species have been observed attacking and killing lions, large ungulates and even sharks.
Crocodiles have a tendency to retain hard, indigestible objects in their stomach and most crocodiles over two metres long have been found to have stones in their stomach. It is believed that the stones are used as gastroliths (to aid in grinding up food) and that they also may function as ballast (just as in a ship's hull). This tendency for retention of hard objects can also confound coroners' inquests where people have been killed by crocodiles. Along with the human remains, bullets are often recovered from the stomachs of large crocodiles. The bullets usually come from other animals that have been shot and have died, and are later eaten by crocodiles. The animals are digested but the bullets remain.
Crocodile
Crocodile
Crocodile
Crocodile
Crocodile
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