Camel - Eagle Heights, Wildlife Park, Kent, England - Sunday September
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From Wikipedia, the free encyclopedia ~ Camels are even-toed ungulates
within the genus Camelus. The dromedary, one-humped or Arabian camel
has a single hump, and the Bactrian camel has two humps. They are
native to the dry desert areas of western Asia, and central and east
The average life expectancy of a camel is forty to fifty years. The term camel is also used more broadly to describe any of the six camellike creatures in the family Camelidae: the two true camels, and the four South American camelids, the llama, alpaca, guanaco, and vicuña.
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 thirty inches (75 cm) out of its body. Camels can run 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, and later spread to Asia.
Humans first domesticated camels before 2000 BC.
The dromedary and the Bactrian camel are both still used for 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.
Distribution and numbers ~ The almost 14 million dromedaries alive
today are domesticated animals (mostly living in Somalia, Sudan,
Mauritania and nearby countries).
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 700,000 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 11% 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 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
Camels do not store water in their humps as is commonly believed; the humps are actually a reservoir of fatty tissue. When this tissue is metabolized, it acts as a source of energy, and would yield 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 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 (100 litres (22 imp gal/26 US gal) to 150 litres (33 imp gal/40 US gal) in one drink).
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) 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 sweating. This ability to fluctuate body temperature and the efficiency of their sweating allows them to preserve about five litres 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 their 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 bodies' 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 the desert sand. 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.