Crocodilians first appeared about 200 million years ago and are believed to be descendants of the great age of reptiles. Their ancestors were lightly built and originally lived on land but were forced to the aquatic life by the larger reptiles. Modern crocodiles spend most of their time in water. The bony plates in the thick skin of the crocodile, called ostreoderms, act as a kind of armour to protect the itself. Several species of crocodile are endangered due to hunting and habitat destruction. The largest crocodile is the saltwater crocodile  which grows up to 23 feet, and weighs up to 2000 pounds. The smallest is the African Dwarf crocodile grows to about 6.2 feet. Crocodiles are carnivores : they eat fish, birds, turtles, frogs and mammals. The female crocodile lays up to 90 eggs and buries them in sand mud or vegetable debris. The  mother or father will stay and guard the eggs with it's life.
the Nile Crocodile
By. Jason O'Grady