Water Ahoy! : A Humpy Tale

Ask most people what they think is the primary function of the weird protrusion or two on the back of a camel, and the likeliest answer would be that the 'hump' is a reservoir of water due to which the camel can survive for days in the hot desert.

Not true.
Surprised? Read on...

Camels, also known as 'ships-of-the-desert' (because they can carry heavy loads, as much as 500 kg) are an amazing creation of nature. It is not their ability to go without water for long periods of time that sets them apart - there are creatures like the 'Kangaroo rat' that are capable of surviving without any free water - but the ways in which they cope with the harsh desert conditions including the severe heat.

Coming back to their humps, camels store 'fat' in them, not water. The humps are emergency food reserves that are used in case of scarcity of food. In fact baby camels do not have a hump, because the layer of fat will not develop till they begin to eat solid food. And in case you still have doubts, find an adult camel, cut its hump and see for yourself - don't blame me for the consequences though.

So how exactly do camels take care of their water requirements? Or do they survive without water?

The answer is that camels store water, not in their humps but in their body fluids, including their blood. Camels can drink up to 200 liters (52.84 gallons) of water at a time, and they are quick drinkers, 100 liters (26.4 gallons) of water in about 10 minutes. And they are not very choosy when it comes to the water, even brackish or salt water will do. This along with their amazing ability to minimize water loss helps them survive. Unlike most warm-blooded creatures, which maintain a constant body temperature, a camel's body temperature changes as per the external temperature. It can vary from 35 degrees C (95 degrees F) to above 40 degrees C (104 degrees F). This helps them to minimize water loss by sweating, as the temperature rises. They also have an unusual ability to avoid dehydration. While most animals would die of dehydration on losing 20% of their body weight in water (excessive loss of body temperature causes thickening of blood, which is almost always fatal) camels can survive a loss in body weight up to 40% without serious consequences.

In case you are wondering why the fat is stored only in the hump and not elsewhere, it is because fat acts as an insulating material preventing heat loss. In the extreme desert conditions, camels need to lose heat freely, so instead of having a layer of fat all around, it is stored in a hump, leaving the rest of the body to freely lose heat.

Camels are of two types; the 'one-humped' camels, also known as the 'Dromedary' camels and the 'two-humped' or the 'Bactrian' camels.

As a species, camels are perfectly adapted to survive in the desert. Each and every part of their body is customized for desert life. Winds in the desert often blow sand into the air, but the camel's long, thick eyelashes protect their eyes from the sand. If some sand does manage to evade the eyelashes, camels have a third eyelid to get rid of the sand; this extra eyelid moves from side to side like a windshield wiper and wipes the sand away. Being very thin, camels can see through the third eyelid. They can thus close this eyelid during a sandstorm and still see; in effect, they can actually walk with closed eyes.

Also camels have hair inside their ears to block sand and can close their nostrils to keep sand out. Their huge feet, which can be as broad as a dish, help them to walk on sand without sinking into it. Parts of the body (including the knee) that touch the hot sand when sitting are toughened or callused. Camels have thick lips and tough lining in their mouth and can thus eat parts of the plants that others do not, such as the thorns of the acacia (A typical African savannah tree covered with long needles). But they are careful to eat only a few leaves from each tree, so as to not leave the trees completely bare.

Even in this mechanical age, camels are considered a strong and reliable means of transport in the desert. Besides transportation, they are a valuable source of milk and meat; their skin is used to make containers for carrying water, their manure as fuel and their wool to knit rugs & tents. No wonder the 'Bedouins' (Nomadic Arabs) call the camels, 'Ata Allah' or 'the gift of God'.