Camelus Linnaeus, 1758
* Camelus on Mammal Species of the World.
A camel is an even-toed ungulate within the genus Camelus, bearing distinctive fatty deposits, known as humps, on its back. There are two species of camels: the dromedary or Arabian camel has a single hump, and the Bactrian camel has two humps. Dromedaries are native to the dry desert areas of West Asia, and Bactrian camels are native to Central and East Asia. Both species are domesticated; they provide milk and meat, and are beasts of burden.
The term camel, (from the Arabic جمل, ǧml, derived from the triconsonantal root signifying "beauty"), 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: the llama, alpaca, guanaco, and vicuña.
The average life expectancy of a camel is 40 to 50 years. A fully grown adult camel stands 1.85 m (6 ft 1 in) at the shoulder and 2.15 m (7 ft 1 in) at the hump. The hump rises about 30 in (76.20 cm) out of its body. Camels can run at up to 65 km/h (40 mph) in short bursts and sustain speeds of up to 40 km/h (25 mph).
Fossil evidence indicates that the ancestors of modern camels evolved in North America during the Palaeogene period (see also Camelops), and later spread to most parts of Asia. The people of ancient Somalia or the Kingdom of Punt first domesticated camels well before 2000 BC.
Distribution and numbers
14 thousand dromedaries alive today are domesticated animals (mostly living in Somalia, the Sahel, Maghreb, Middle East and Indian subcontinent). An estimated quarter of the world's camel population is found in Somalia and in the Somali Region of Ethiopia, where the camel is an important part of nomadic Somali life. They provide the Somali people with milk, food and transportation.
The Bactrian camel 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 in China and Mongolia.
There is a substantial feral population of dromedaries estimated at up to 1,000,000 in central parts of Australia, descended from individuals introduced as transport animals in the 19th century and early 20th century. This population is growing at approximately 18% per year. The 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 second half of the 20th Century. These animals, imported from Turkey, were part of the U.S. 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.
Camels do not store water in their humps as is commonly believed. The humps are actually a reservoir of fatty tissue. Concentrating body fat in their humps minimizes heat-trapping insulation throughout the rest of their body, which may be an adaptation to living in hot climates. When this tissue is metabolized, it acts as a source of energy, and yields more than 1 g of water for each 1 g of fat converted through reaction with oxygen from air. This process of fat metabolization generates a net loss of water through respiration for the oxygen required to convert the fat.
Their ability to withstand long periods without water is due to a series of physiological adaptations. Their red blood cells have an oval shape, unlike those of other mammals, which are circular. This facilitates 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 (100 litres (22 imp gal; 26 US gal) to 150 litres (33 imp gal; 40 US gal) in one drink). Oval red corpuscles are not found in any other mammal, but are present in reptiles, birds, and fish.
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 and up to 41 °C (106 °F) during the 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 perspiration.
They can withstand at least 20-25% weight loss due to sweating (most mammals can only withstand about 15% dehydration before cardiac failure results from circulatory disturbance). 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 bodies' hydrated state without the need for drinking.
A camel's thick coat reflects sunlight, and also insulates it from the intense heat radiated from desert sand. A shorn camel has to sweat 50% more to avoid overheating. Their long legs help by keeping them further from the hot ground. Camels have been known to swim.
Their mouth is very sturdy, able to chew thorny desert plants. Long eyelashes and ear hairs, together with sealable nostrils, form a barrier against sand. Their gait and their widened feet help them move without sinking into the sand.
The kidneys and intestines of a camel are very efficient at retaining water. Urine comes out as a thick syrup, and their feces are so dry that they can fuel fires.
All camelids have an unusual immune system. In all mammals, the Y-shaped antibody molecules consist of two heavy (or long) chains along the length of the Y, and two light (or short) chains at each tip of the Y. Camels also have antibody molecules that have only two heavy chains, which makes them smaller and more durable. These heavy chain-only antibodies, which were discovered in 1993, probably developed 50 million years ago, after camelids split from ruminants and pigs, according to biochemist Serge Muyldermans.
The camel is the only animal to have replaced the wheel (mainly in North Africa) where the wheel had already been established. The camel did not lose that distinction until the wheel was combined with the internal combustion engine in the 20th century.
The karyotypes of different camelid species have been studied earlier by many groups, but no agreement on chromosome nomenclature of camelids has been reached. The most recent study used flow-sorted camel chromosomes building undoubtedly the camel`s karyotype (2n=74) that consists of one metacentric, three submetacentric and 32 acrocentric autosomes. The Y is a small metacentric chromosome, while the X is a large metacentric chromosome. According to molecular data, the New World and Old World camelids diverged 11 MYA. In spite of this, these species turned out to be conserved sufficiently to hybridize and produce live offspring(cama). The dromedary-guanaco inter-specific hybrid provided the ideal platform to compare the karyotypes of Old World and New World camels.
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 attracted to 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.
Dromedary-Bactrian 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.
Since at least 1200 BC, the first camel saddles appeared, and Bactrian camels could be ridden. The first Arabian saddle was put way to the back of the camel, and control of the Bactrian camel happened by means of a stick. However it wasn't until between 500-100 BC that Bactrian camels finally attained a military use. These new saddles were put over the humps of the animal, and they were also inflexible and bent, dividing the weight sufficiently over the animal. In the seventh century D.C., the military Arabian saddle then appeared, which improved the saddle design again slightly.
Camel cavalry have been used in wars throughout Africa, the Middle East and into modern-day India. Armies have also used camels as freight animals instead of horses and mules.
In the East Roman Empire the Romans used auxiliary forces known as Dromedarii, whom they recruited in desert provinces. The camels were mostly used in combat because of their ability to scare off horses in close ranges, a quality famously employed by the Achaemenid Persians when fighting Lydia, although the Persians usually used camels as baggage trains for arrows and equipment.
19th and 20th Centuries
* The United States Army established the U.S. Camel Corps, which was stationed in California in the 19th century. One may still see brick stables at the Benicia Arsenal in Benicia, California, where they serve as artists' and artisans' studio spaces. During the American Civil War, camels were used at an experimental stage, but were not used any further, as they were unpopular with the men. Some escaped and their descedants roamed the arid parts of the American West until as late as the early 20th century.
Camel milk cannot be made into butter by the traditional churning method. It can be made if it is soured first, churned, and a clarifying agent added, or if it is churned at 24–25 °C (75–77 °F), but times vary greatly in achieving results. Until recently, camel milk could not be made into cheese because rennet was unable to coagulate the milk proteins to allow the collection of curds. Under the commission of the FAO, Professor J.P. Ramet of the École Nationale Supérieure d'Agronomie et des Industries Alimentaires (ENSAIA) was able to produce curdling by the addition of calcium phosphate and vegetable rennet. The cheese produced from this process has low levels of cholesterol and lactose. The sale of camel cheese is limited owing to the low yield of cheese from milk and the uncertainty of pasteurization levels for camel milk, which makes adherence to dairy import regulations difficult.
A camel carcass can provide a substantial amount of meat. The male dromedary carcass can weigh 400 kg (900 lb) or more, while the carcass of a male Bactrian can weigh up to 650 kg (1,400 lb). The carcass of a female camel (or she-camel) weighs less than the male, ranging between 250 and 350 kg (550 and 770 lb). The brisket, ribs and loin are among the preferred parts, but the hump is considered a delicacy and is most favored. It is reported that camel meat tastes like coarse beef, but older camels can prove to be very tough and less flavorful. The meat from older camels is best prepared by slow cooking. Camel meat is low in fat, and can thus taste dry. The Abu Dhabi Officers' Club serves a camel burger, as this allows the meat to be mixed with beef or lamb fat, improving both the texture and taste. In Karachi, Pakistan the exclusive Nihari restaurants prepare this dish from camel meat, while the general restaurants prepare it with either beef or water buffalo meat.
Camel meat has been eaten for centuries. It has been recorded by ancient Greek writers as an available dish in ancient Persia at banquets, usually roasted whole. The ancient Roman emperor Heliogabalus enjoyed camel's heel. Camel meat is still eaten in certain regions including Somalia, where it is called Hilib geel, Saudi Arabia, Egypt, Libya, Sudan, Kazakhstan and other arid regions where alternative forms of protein may be limited or where camel meat has had a long cultural history. In the Middle East, camel meat is the rarest and most prized source of pastırma. Not just the meat, but also blood is a consumable item as is the case in northern Kenya, where camel blood is a source of iron, vitamin D, salts and minerals. Camel meat is also occasionally found in Australian cuisine, for example, a camel lasagne is available in Alice Springs.
A 2005 report issued jointly by the Saudi Ministry of Health and the United States Center for Disease Control details cases of human bubonic plague resulting from the ingestion of raw camel liver.
In Sunni Islam, the Sahih Bukhari, which forms one of the six major Hadith collections quotes the Prophet Muhammad advocating drinking camel's milk and urine as medicine in several verses.
Camel meat is halal for Muslims but - unusually for a halal food - anyone eating it must renew their wudhu (ritual ablution) before prayer.
According to Jewish tradition, camel meat and milk are not kosher. Camels possess only one of the two Kosher criteria; although they chew their cuds, they do not possess cloven hooves (See: Taboo food and drink).
1. ^ Scarre, Chris (1993-09-15). Smithsonian Timelines of the Ancient World. London: D. Kindersley. p. 176. ISBN 978-1564583055. "Both the dromedary (the seven-humped camel of Arabia) and the Bactrian camel (the two-humped camel of Central Asia) had been domesticated since before 2000 BC."
* Vannithone S, Davidson A (1999). "Camel". The Oxford companion to food. Oxford Oxfordshire: Oxford University Press. p. 127. ISBN 0-19-211579-0.
Source: Wikipedia, Wikispecies: All text is available under the terms of the GNU Free Documentation License