Camels can survive for days in deserts with little food and no water due to their unique physiology. Contrary to the common belief, a camel does not store water in its stomach or its hump. Instead the hump stores fat which serves as a reserve for energy and a source of water when in need. When the fat is utilized by the camel’s body, hydrogen is released which combines with oxygen to form water. Camels also use water from other body tissues in a similar way. As body tissues dehydrate, it can lose as much as 25 per cent of its body weight without suffering any permanent damage. But when it does find water, a thirsty camel may drink up to 150 litres in 15 minutes. The water passes rapidly into its body tissues, making the animal fit for another desert crossing.