Camels are experts at living where food and water are scarce. The reason they can survive in such arid terrain is their amazing ability to conserve the water they do take on. When a dehydrated camel finds a water source, it can lap up as much as 120 litres (32 gallons) in 15 minutes. To conserve the lifesaving H2O, camels can regulate their body temperature so that they hardly sweat at all. Their kidneys can concentrate the urine to further reduce water loss.
Not only this but these creatures also store a lot of water in their blood; the erythrocytes (red blood cells) can swell to over twice their normal size without bursting. Thanks to this tailored physiology, camels can go for weeks with little to no food or water.
However, when sustenance is in seriously short supply, they make use of a secret energy stash on their backs. The camel’s hump does not store water; it functions as a reserve of adipose tissue (fat cells) that can metabolise to provide emergency energy. As the fat is depleted, the hump will begin to wilt and flop to one side.
These fatty humps are great for keeping cool too as fat conducts the Sun’s heat relatively slowly, and their woolly covering provides extra insulation.