A camel's hump is not filled with water, as some people think. It is filled with fat - up to 36 kilograms of it. When food is hard to find, the camel's body uses up the fat in the hump, slowly, like a built-in lunchbox. A camel that hasn't eaten for a long time has a floppy, leaning hump.
Camels are amazing with water. They can drink up to 100 litres in one go - that's about 200 large drink bottles - and then go more than a week without drinking again. Their bodies are so good at saving water that they barely sweat, even in the desert sun.
Their feet are wide and soft, like cushions. They spread out as the camel steps down, so it doesn't sink into the sand. They have two layers of long eyelashes, ears full of hair, and nostrils they can close - all to keep sand out during desert storms.
Camels can carry heavy loads for days without complaining. In Egypt and across the Sahara, people have travelled with camels for over 3,000 years. Long camel journeys are still called 'caravans' - and that is exactly where the English word came from.