Camels are even-toed ungulates in the genus Camelus. The Dromedary or Arabian Camel has a single hump, and the Bactrian Camel has two humps. They are native to the dry and desert areas of western Asia and East Africa, and central and east Asia, respectively. The average life expectancy of a camel is 50 to 60 years. The term camel is also used more broadly to describe any of the six camel-like creatures in the family Camelidae: the two true camels, and the four South American camelids: Llama, Alpaca, Guanaco, and Vicuña.
The name camel comes to English via the Greek κάμηλος (kámēlos) from
the Hebrew gamal or Arabic "Jamal".
Bactrian camels have two coats: the warm inner coat of down and a rough outer coat which is long and hairy. They shed their fibre in clumps consisting of both coats, which can be gathered and separated. They produce approximately 7 kg (15 lb) of fiber annually. The fiber structure is similar to cashmere wool. The down is usually 2 to 8 cm (1–3 inches) long. While camel down does not felt easily, it may be spun into a yarn for knitting.
A fully-grown adult camel stands 1.85m/6 feet at the shoulder and 2.15m/7 feet at the hump. The hump rises about 30 inches out of its body. Camels can run up to 40mph in short bursts, and sustain speeds of up to 25mph.
Humans first domesticated camels between 3,500–3,000 years ago. The Dromedary and the Bactrian Camel are both still used for milk (which is more nutritious than cow's milk), meat, and as beasts of burden—the Dromedary in western Asia, and the Bactrian Camel further to the north and east in central Asia.
Camel headcount in 2003The almost 14 million Dromedaries alive today are domesticated animals (mostly in Somalia, Sudan, Mauritania and nearby countries).
The Bactrian Camel once had an enormous range, but is now reduced to an estimated 1.4 million animals, mostly domesticated. It is thought that there are about 1000 wild Bactrian Camels in the Gobi Desert, and small numbers in Iran, Afghanistan and Kazakhstan.
There is a substantial feral population estimated at up to 700,000 in central parts of Australia, descended from individuals introduced as means of transport in the 19th century and early 20th century. This population is growing at approximately 11% per year and in recent times the state government of South Australia has decided to cull the animals using aerial marksmen, because the camels use too much of the limited resources needed by sheep farmers. For more information, see Australian feral camel. A small population of introduced camels, Dromedaries and Bactrians, survived in the Southwest United States until the 1900s. These animals, imported from Turkey, were part of the US Camel Corps experiment and used as draft animals in mines, and escaped or were released after the project was terminated. A descendant of one of these was seen by a backpacker in Los Padres National Forest in 1972. Twenty-three Bactrian camels were brought to Canada during the Cariboo Gold Rush.
Throughout their domesticated history, Camels have been used as a means of transportation in arid regions. Shown here is a local tribe near Jaisalmer, Rajasthan, India.
Bactrian Camels have two humps and are rugged cold-climate camels while Dromedaries have one hump and are desert dwellers. Dromedary hybrids are called Bukhts, are larger than either parent, have a single hump and are good draft camels. The females can be mated back to a Bactrian to produce ¾-bred riding camels. These hybrids are found in Kazakhstan. The Cama is a camel/llama hybrid bred by scientists who wanted to see how closely related the parent species were. The Dromedary is six times the weight of a Llama, hence artificial insemination was required to impregnate the Llama female (Llama male to Dromedary female attempts have proven unsuccessful). Though born even smaller than a Llama cria, the Cama had the short ears and long tail of a camel, no hump and Llama-like cloven hooves rather than the Dromedary-like pads. At four years old, the Cama became sexually mature and interested in Llama and Guanaco females. A second Cama (female) has since been produced using artificial insemination. Because Camels and Llamas both have 74 chromosomes, scientists hope that the Cama will be fertile. If so, there is potential for increasing size, meat/wool yield and pack/draft ability in South American camels. The Cama apparently inherited the poor temperament of both parents as well as demonstrating the relatedness of the New World and Old World camelids.
Camels are well known for their humps. They do not, however, store water in them as is commonly believed, though they do serve this purpose through roundabout means. Their humps are a reservoir of fatty tissue. However, when this tissue is metabolized, it is not only a source of energy, but yields through reaction with oxygen from the air 1,111 g of water per 1,000 g of fat converted. Though this metabolized of the fat generates a net loss of water through respiration during the process.
Their ability to withstand long periods without water is due to a series of physiological adaptations, as described below.
Their red blood cells have an oval shape, unlike those of other mammals, which are circular. This is to facilitate their flow in a dehydrated state. These cells are also more stable, in order to withstand high osmotic variation without rupturing, when drinking large amounts of water (20-25 gallons in one drink).
The kidneys of a camel are very efficient. Urine comes out as a thick syrup and their feces are so dry that they can fuel fires.
Camels are able to withstand changes in body temperature and water content that would kill most other animals. Their temperature ranges from 34°C (93°F) at night up to 41°C (106°F) at day, and only above this threshold will they begin to sweat. The upper body temperature range is often not reached during the day in milder climatic conditions and therefore the camel may not sweat at all during the day. Evaporation of their sweat takes place at the skin level not at the surface of their coat, thereby being very efficient at cooling the body compared to the amount of water lost through sweating. This ability to fluctuate body temperature and the efficiency of their sweating allows them to preserve about five liters of water a day.
A feature of their nostrils is that a large amount of water vapor in their exhalations is trapped and returned to the camels body fluids, thereby reducing the amount of water lost through respiration.
They can withstand at least 20-25% weight loss due to sweating (most mammals can only withstand about 3-4% dehydration before cardiac failure results from the thickened blood). A camel's blood remains hydrated even though the body fluids are lost; until this 25% limit is reached.
Camels eating green herbage can ingest sufficient moisture in milder conditions to maintain their body's hydrated state without the need for drinking.
A camel's thick coat reflects sunlight. A shorn camel has to
sweat 50% more to avoid overheating. It also insulates them from
the intense heat that radiates from hot desert sand. Their long
legs help by keeping them further from the hot ground. Camels
have been known to swim if given the chance.
Their mouth is very sturdy, able to chew thorny desert plants. Long eyelashes and ear hairs, together with sealable nostrils, form an effective barrier against sand. Their pace (moving both legs on one side at the same time) and their widened feet help them move without sinking into the sand.
All member species of the Camelids are known to have a highly unusual immune system, where part of the antibody repertoire is composed of immunoglobulin without light chain. Whether and how this contributes to their resistance to harsh environments is currently unknown.
Not a behavioral aspect of the camel, but of genuine interest, is the fact that the camel is the only animal to have replaced the wheel (mainly in North Africa) where the wheel had already been established. The camel was not removed from the top of the transport industry in these areas until the wheel was combined with the internal combustion engine in the 20th century.
This Camel Page is Copyright The Animal Web Guide © 2004 - 2009 Chuck Ayoub