The short answer

Camels have humps to provide them an emergency energy source and to effectively distribute body heat. Contrary to popular belief, camels' humps do not store water. Instead the humps are made up of concentrated fat that can be used for fuel.

The long answer

Camels are known for their ability to last extremely long periods of time in hot, arid desert conditions. And it's a popular myth that these humps (either one or two humps, depending on the species) store water for the camel to absorb when there is no water to be found. However camel humps are actually made up of fat, and they serve two purposes: an emergency energy source and better temperature regulation.

Camels are able to metabolize the fat stored in their humps to go long periods of time without food. Each hump can store up to 80 pounds of fat.

Additionally, by concentrating the fat in prominent humps, camels are able to reduce heat insulation on hot days. If the extra fat they stored was evenly distributed around their body, it would cause them to overheat. Moreover, when the temperature drops at night, the extra heat stored in the humps is able to keep them warm.

🧠 Bonus brain points

How are camels able to last without water?

Camels' ability to go long periods of time without water is thought to be due to the unique, oval shape of their red blood cells. Oval-shaped red blood cells are more elastic and can change shape more easily, which allows blood to flow more easily in thick blood when water is scarce. Their red blood cells are also able to significantly expand during rehydration. This is why a camel can drink up to 30 gallons in 10 minutes!

Sources

The Biomimicry Institute. (2016, September 14). Blood Cells Protect From Dehydration: Dromedary camel. AskNature. Retrieved February 12, 2023, from https://asknature.org/strategy/blood-cells-protect-from-dehydration/

Chase, M. (2019). Camel Anatomy; More Than Just a Hump. St. John Fisher University. Retrieved February 12, 2023, from https://fisherpub.sjf.edu/cgi/viewcontent.cgi?article=1254&context=ur

Crupi, S. (2021, April 6). Truth or Tail: A camel's hump. Cleveland Zoological Society. Retrieved February 12, 2023, from https://www.clevelandzoosociety.org/z/2021/04/06/truth-or-tail-a-camels-hump

Gonzalez, N. (n.d.). Do Camels Store Water in Their Humps? Encyclopædia Britannica. Retrieved February 12, 2023, from https://www.britannica.com/story/do-camels-store-water-in-their-humps