They are reptiles so they have scaly skin. Their backs have notchy scales with blocks of bone inside. This is like protective armour.
Their sharp teeth aren't used for chewing, just for holding onto food.
Food is generally swallowed whole or in large chunks
Crocodiles are lucky. If they lose teeth they just regrow.
The strong tail can be used as a weapon to deliver a powerful blow.
The tail can also be used to push a crocodile straight up out of the water to grab some poor bird sitting on a low branch.
The tail also makes it a good swimmer. The swimming motion is like a wave from head to tail.
Crocodiles can live on the land and in the water.
In the water most of the body is hidden. You can only see the nostrils and the eyes above the water.
That way the crocodile can breathe and see any delicious meal that might come near the water's edge.
With so little showing above the water it's hard to tell how big it is.
Crocodiles eat almost anything, but they prefer meat. Fruit and vegetables aren't their favourite food.
Like most reptiles, crocodiles lay eggs.
The female lays them in the sand or under rotting leaves. She covers them to protect them from hungry snakes, birds, goannas or even other crocodiles. These animals like to eat crocodile eggs.
When they are ready to hatch the baby crocodiles make a yapping sound from inside the eggs. This lets mum know her babies are ready to hatch so she digs them up and if they are having trouble getting out of their shells, she helps them by rolling the eggs inside her mouth and gently squeezing them until they hatch.
Mum may also carry her babies to water.
The baby crocodiles have to find insects to eat. Mum protects them for a month or two, but then they are completely on their own.
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