Why do camels have humps?
Camels' humps store fat, not water. The fat can be broken down for energy when food is scarce, and storing it in one place helps the rest of the body stay cool.
A camel's hump can hold up to about 35 kilograms of fat. When food is hard to find in the desert, the camel uses this fat as an energy reserve. As the fat is used up, the hump becomes smaller and may flop over to one side. After the camel eats and rests, it fills out again.
Keeping fat concentrated in the hump rather than spread under the skin helps camels lose heat more easily from the rest of their bodies. This is useful in hot deserts, where staying cool is important for survival.
One hump or two?
Dromedary camels, found in the Middle East and North Africa, have one hump. Bactrian camels, from the cold deserts of Central Asia such as the Gobi, have two humps. Wild Bactrian camels are critically endangered, with only around 1,000 left in China and Mongolia.
Did You Know?
Camels have thick lips that let them eat thorny desert plants, and they can close their nostrils to keep out blowing sand.