| Camel | |
|---|---|
| Dromedary, Camelus dromedarius | |
| Bactrian Camel, Camelus bactrianus | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Family: | Camelidae |
| Tribe: | Camelini |
| Genus: | Camelus Linnaeus, 1758 |
| range of dromedary and bactrians
Camelus bactrianus |
|
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 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 working animals.
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.[1][2]
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The 14 million dromedaries alive today are domesticated animals (mostly living in the Horn of Africa, the Sahel, Maghreb, Middle East and the Indian subcontinent). The Horn region alone has the largest concentration of camels in the world,[3] where the dromedaries constitute an important part of local nomadic life. They provide peripatetic Somali and Ethiopian 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 1,000 wild Bactrian camels in the Gobi Desert in China and Mongolia.[4]
There is a substantial feral population of dromedaries estimated[5] 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 8% per year.[6] The government of South Australia has recently decided to cull the animals using aerial marksmen, in part 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. 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.[7] 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.[8]
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[9] 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).[10] Oval red corpuscles are not found in any other mammal, but are present in reptiles, birds, and fish.[11]
Camels are able to withstand changes in body temperature and water consumption 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.
A feature of their nostrils is that a large amount of water vapor in their exhalations is trapped and returned to their body fluids, thereby reducing the amount of water lost through respiration.[12]
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.[13]
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.[14]
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.[15]
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.[16]
The karyotypes of different camelid species have been studied earlier by many groups,[17][18][19][20][21][22] 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.[23]
According to molecular data, the New World and Old World camelids diverged 11 MYA.[24] In spite of this, these species turned out to be conserved sufficiently to hybridize and produce live offspring(cama).[25] 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.[26]
By at least 1200 BC, the first camel saddles had 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 was exercised 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 BC, the military Arabian saddle appeared, which improved the saddle design again slightly.[27]
Camel cavalry have been used in wars throughout Africa, the Middle East and into modern-day Border Security Force of 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 at close ranges, a quality famously employed by the Achaemenid Persians when fighting Lydia, although the Persians usually used camels in baggage trains for arrows and equipment.
Camel milk is a staple food of desert nomad tribes and is considered a whole food, nomads requiring nothing but camel milk for up to six months. Camel milk is rich in vitamins, minerals, proteins and immunoglobulins. It is lower in fat and cholesterol fat than cow milk. It is said to have many healthful properties and is used as a medicinal product in India, Mongolia, Kazakhstan, Africa and the Middle East. It is also used as an aphrodisiac in these countries, an example being Ethiopia. Bedouins believe that the curative powers of camel milk are enhanced if the camel's diet consists of certain desert plants. Camel milk can readily be made into a drinkable yogurt, but does not set as it has fewer milk solids than cow or goat's milk. Camel milk cream can be separated and made into butter or cheese but the yields will be low in comparison to buffalo or cow cream, again due to the low content of fat and solids.
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 camel 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.[28] The cheese produced from this process has low levels of cholesterol and is easy to digest, even for the lactose intolerant. The sale of camel cheese is limited owing to the small output of the single dairy currently producing camel cheese and the absence of camel cheese in most camel cultures. Cheese imports from countries that traditionally breed camels are difficult to obtain due to restrictions on dairy imports from these regions.
Camel milk has been made into ice cream on a camel farm in the Netherlands.[29]
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.[30]
Camel meat is halal for Muslims; however, according to some Islamic schools of thought, a state of impurity is brought on by the consumption of it. Consequently, they hold that Muslims must perform wudhu before praying.[31]
There are Islamic traditions that allow the drinking of urine for medicinal purposes. However, these traditions have varying levels of authentication within Islamic scholarship.[32][33]
Also, some Islamic schools of thought consider it haraam for a Muslim to perform salah in places where camels lie as it is said to be a dwelling place of shaytan.[31]
According to Jewish tradition, camel meat and milk are not kosher. Camels possess only one of the two Kosher criteria; although they chew their cud, they do not possess cloven hooves (See: Taboo food and drink).[34]
| “ | Nevertheless these shall ye not eat of them that only chew the cud, or of them that only part the hoof: the camel, because he cheweth the cud but parteth not the hoof, he is unclean unto you.Leviticus 11:4 | ” |