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The dromedary (''Camelus dromedarius'' or ;), also known as the dromedary camel, Arabian camel, or one-humped camel, is a large
even-toed ungulate The even-toed ungulates (Artiodactyla , ) are ungulates—hoofed animals—which bear weight equally on two (an even number) of their five toes: the third and fourth. The other three toes are either present, absent, vestigial, or pointing poster ...
, of the genus ''
Camelus A camel (from: la, camelus and grc-gre, κάμηλος (''kamēlos'') from Hebrew or Phoenician: גָמָל ''gāmāl''.) is an even-toed ungulate in the genus ''Camelus'' that bears distinctive fatty deposits known as "humps" on its back. C ...
'', with one hump on its back. It is the tallest of the three species of camel; adult males stand at the shoulder, while females are tall. Males typically weigh between , and females weigh between . The species' distinctive features include its long, curved neck, narrow chest, a single hump (compared with two on the
Bactrian camel The Bactrian camel (''Camelus bactrianus''), also known as the Mongolian camel or domestic Bactrian camel, is a large even-toed ungulate native to the steppes of Central Asia. It has two humps on its back, in contrast to the single-humped dro ...
and wild Bactrian camel), and long hairs on the throat, shoulders and hump. The coat is generally a shade of brown. The hump, tall or more, is made of fat bound together by
fibrous tissue Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...
. Dromedaries are mainly active during daylight hours. They form herds of about 20 individuals, which are led by a dominant male. They feed on foliage and desert vegetation; several adaptations, such as the ability to tolerate losing more than 30% of its total water content, allow it to thrive in its desert habitat. Mating occurs annually and peaks in the rainy season; females bear a single calf after a gestation of 15 months. The dromedary has not occurred naturally in the wild for nearly 2,000 years. It was probably first
domesticated Domestication is a sustained multi-generational relationship in which humans assume a significant degree of control over the reproduction and care of another group of organisms to secure a more predictable supply of resources from that group. A ...
in the Arabian Peninsula about 4,000 years ago, or in
Somalia Somalia, , Osmanya script: 𐒈𐒝𐒑𐒛𐒐𐒘𐒕𐒖; ar, الصومال, aṣ-Ṣūmāl officially the Federal Republic of SomaliaThe ''Federal Republic of Somalia'' is the country's name per Article 1 of thProvisional Constituti ...
where there are paintings in
Laas Geel Laas Geel ( so, Laas Geel), also spelled Laas Gaal, are cave formations on the rural outskirts of Hargeisa, Somaliland, situated in the Maroodi Jeex region of the country. They contain some of the earliest known cave paintings of domesticated Afr ...
that figure it from 5,000 to 9,000 years ago. In the wild, the dromedary inhabited arid regions, including the
Sahara Desert , photo = Sahara real color.jpg , photo_caption = The Sahara taken by Apollo 17 astronauts, 1972 , map = , map_image = , location = , country = , country1 = , ...
. The domesticated dromedary is generally found in the semi-arid to arid regions of the Old World, mainly in Africa and the Arabian Peninsula, and a significant feral population occurs in Australia. Products of the dromedary, including its meat and milk, support several North African tribes; it is also commonly used for riding and as a pack animal.


Etymology

The common name "dromedary" comes from the
Old French Old French (, , ; Modern French: ) was the language spoken in most of the northern half of France from approximately the 8th to the 14th centuries. Rather than a unified language, Old French was a linkage of Romance dialects, mutually intellig ...
''dromedaire'' or the
Late Latin Late Latin ( la, Latinitas serior) is the scholarly name for the form of Literary Latin of late antiquity.Roberts (1996), p. 537. English dictionary definitions of Late Latin date this period from the , and continuing into the 7th century in t ...
''dromedarius''. These originated from the
Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...
word ''dromas'', δρομάς (ο, η) ( GEN (γενική) ''dromados'', δρομάδος), meaning "running" or "runner",. used in Greek in the combination (''dromas kamelos''), literally "running camel", to refer to the dromedary. The first recorded use in English of the name "dromedary" occurred in the 14th century. The dromedary possibly originated in Arabia or Somalia and is therefore sometimes referred to as the Arabian or East African camel. The word "camel" generally refers either to the dromedary or the
congeneric Congener may refer to: * A thing or person of the same kind as another, or of the same group. * Congener (biology), organisms within the same genus. * Congener (chemistry), related chemicals, e.g., elements in the same group of the periodic table. ...
Bactrian; the word came into English via
Old Norman Old Norman, also called Old Northern French or Old Norman French ( fro, Ancien Normant, nrf, Ancien Normaund), was one of many varieties of the ''langues d'oïl'' native to northern France. It was spoken throughout the region of what is now calle ...
, from the
Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
word ''camēlus'', from
Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...
(''kámēlos''), ultimately from a Semitic source akin to
Hebrew Hebrew (; ; ) is a Northwest Semitic language of the Afroasiatic language family. Historically, it is one of the spoken languages of the Israelites and their longest-surviving descendants, the Jews and Samaritans. It was largely preserved ...
(''gamál'') and
Arabic Arabic (, ' ; , ' or ) is a Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C. E.Watson; Walter ...
(''jamal'').


Taxonomy and classification

The dromedary shares the
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
''
Camelus A camel (from: la, camelus and grc-gre, κάμηλος (''kamēlos'') from Hebrew or Phoenician: גָמָל ''gāmāl''.) is an even-toed ungulate in the genus ''Camelus'' that bears distinctive fatty deposits known as "humps" on its back. C ...
'' with the Bactrian camel (''C. bactrianus'') and the wild Bactrian camel (''C. ferus''). The dromedary belongs to the family Camelidae. The
ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...
philosopher
Aristotle Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of ph ...
(4th century BC) was the first to describe the species of ''Camelus''. He named two species in his ''
History of Animals ''History of Animals'' ( grc-gre, Τῶν περὶ τὰ ζῷα ἱστοριῶν, ''Ton peri ta zoia historion'', "Inquiries on Animals"; la, Historia Animalium, "History of Animals") is one of the major texts on biology by the ancient Gr ...
''; the one-humped Arabian camel and the two-humped Bactrian camel. The dromedary was given its current binomial name ''Camelus dromedarius'' by Swedish zoologist
Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalise ...
in his 1758 publication '' Systema Naturae''. In 1927, British veterinarian Arnold Leese classified dromedaries by their basic habitats; the hill camels are small, muscular animals and efficient beasts of burden; the larger plains camels could be further divided into the desert type that can bear light burdens and are apt for riding, and the riverine type – slow animals that can bear heavy burdens; and those intermediate between these two types. In 2007, Peng Cui of the
Chinese Academy of Sciences The Chinese Academy of Sciences (CAS); ), known by Academia Sinica in English until the 1980s, is the national academy of the People's Republic of China for natural sciences. It has historical origins in the Academia Sinica during the Republi ...
and colleagues carried out a
phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
study of the evolutionary relationships between the two
tribes The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English is in the discipline of anthropology. This definition is contested, in part due to confli ...
of Camelidae;
Camelini Camelini is a tribe of terrestrial herbivores in the family Camelidae, endemic to Asia, North America, and Africa from the Late Eocene to the present. It includes the living genus ''Camelus'' as the type genus. At least one genus, ''Eulamaops'', ...
– consisting of the three ''Camelus'' species (the study considered the wild Bactrian camel as a subspecies of the Bactrian camel) – and Lamini, which consists of the
alpaca The alpaca (''Lama pacos'') is a species of South American camelid mammal. It is similar to, and often confused with, the llama. However, alpacas are often noticeably smaller than llamas. The two animals are closely related and can success ...
(''Vicugna pacos''), the
guanaco The guanaco (; ''Lama guanicoe'') is a camelid native to South America, closely related to the llama. Guanacos are one of two wild South American camelids, the other being the vicuña, which lives at higher elevations. Etymology The guanaco ...
(''Lama guanicoe''), the
llama The llama (; ) (''Lama glama'') is a domesticated South American camelid, widely used as a meat and pack animal by Andean cultures since the Pre-Columbian era. Llamas are social animals and live with others as a herd. Their wool is soft ...
(''L. glama'') and the
vicuña The vicuña (''Lama vicugna'') or vicuna (both , very rarely spelled ''vicugna'', its former genus name) is one of the two wild South American camelids, which live in the high alpine areas of the Andes, the other being the guanaco, which live ...
(''V. vicugna''). The study showed the two tribes had diverged 25 million years ago (early
Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...
), earlier than previously estimated from North American fossils. The dromedary and the Bactrian camel often interbreed to produce fertile offspring. Where the ranges of the species overlap, such as in northern Punjab, Persia, and Afghanistan, the phenotypic differences between them tend to decrease as a result of extensive crossbreeding. The fertility of their hybrid has given rise to speculation that the dromedary and the Bactrian camel should be merged into a single species with two varieties. However, a 1994 analysis of the mitochondrial
cytochrome b Cytochrome b within both molecular and cell biology, is a protein found in the mitochondria of eukaryotic cells. It functions as part of the electron transport chain and is the main subunit of transmembrane cytochrome bc1 and b6f complexes. F ...
gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
showed the species display 10.3% divergence in their
sequences In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is called t ...
.


Genetics and hybrids

The dromedary has 74 diploid chromosomes, the same as other camelids. The autosomes consist of five pairs of small to medium-sized metacentrics and submetacentrics. The
X chromosome The X chromosome is one of the two sex-determining chromosomes (allosomes) in many organisms, including mammals (the other is the Y chromosome), and is found in both males and females. It is a part of the XY sex-determination system and XO sex ...
is the largest in the metacentric and submetacentric group. There are 31 pairs of
acrocentric The centromere links a pair of sister chromatids together during cell division. This constricted region of chromosome connects the sister chromatids, creating a short arm (p) and a long arm (q) on the chromatids. During mitosis, spindle fibers ...
s. The dromedary's karyotype is similar to that of the Bactrian camel. Camel hybridization began in the first millennium BC. For about a thousand years, Bactrian camels and dromedaries have been successfully bred in regions where they are sympatric to form hybrids with either a long, slightly lopsided hump or two humps – one small and one large. These hybrids are larger and stronger than their parents – they can bear greater loads. A cross between a first generation female hybrid and a male Bactrian camel can also produce a hybrid. Hybrids from other combinations tend to be bad-tempered or
runt In a group of animals (usually a litter of animals born in multiple births), a runt is a member which is significantly smaller or weaker than the others. Owing to its small size, a runt in a litter faces obvious disadvantage, including difficult ...
s.


Evolution

The extinct '' Protylopus'', which occurred in North America during the upper
Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...
, is the oldest and the smallest-known camel. During the transition from
Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...
, several mammals faced extinction. This period marked the successful radiation of the ''Camelus'' species, which migrated over the Bering Strait and dispersed widely into Asia, eastern Europe and Africa. By the Pleistocene, ancestors of the dromedary occurred in the Middle East and northern Africa. The modern dromedary probably evolved in the hotter, arid regions of western Asia from the Bactrian camel, which in turn was closely related to the earliest Old World camels. This hypothesis is supported by the fact that the dromedary
foetus A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal develo ...
has two humps, while in the adult male an anterior
vestigial Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on co ...
hump is present. A jawbone of a dromedary that dated from 8,200 BC was found in Saudi Arabia on the southern coast of the
Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; ...
. In 1975,
Richard Bulliet Richard W. Bulliet (born 1940) is a professor of history at Columbia University who specializes in the history of Islamic society and institutions, the history of technology, and the history of the role of animals in human society. Early life ...
of
Columbia University Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...
wrote that the dromedary exists in large numbers in areas from which the Bactrian camel has disappeared; the converse is also true to a great extent. He said this substitution could have taken place because of the heavy dependence on the milk, meat and wool of the dromedary by Syrian and Arabian nomads, while the Asiatic people domesticated the Bactrian camel but did not have to depend upon its products.


Characteristics

The dromedary is the tallest of the three camel species. Adult males range in height between at the shoulder;
Guinness World Records ''Guinness World Records'', known from its inception in 1955 until 1999 as ''The Guinness Book of Records'' and in previous United States editions as ''The Guinness Book of World Records'', is a reference book published annually, listing world ...

Largest species of camel
/ref> females range between . Males typically weigh between ; females range between . The distinctive features are its long, curved neck, narrow chest and single hump (the Bactrian camel has two), thick, double-layered eyelashes and bushy eyebrows. They have sharp vision and a good sense of smell. The male has a soft
palate The palate () is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but in most other tetrapods, the oral and nasal cavities are not truly separ ...
( in Arabic) nearly long, which he inflates to produce a deep pink sac. The palate, which is often mistaken for the tongue, dangles from one side of the mouth and is used to attract females during the mating season. The coat is generally brown but can range from black to nearly white. Leese reported
piebald A piebald or pied animal is one that has a pattern of unpigmented spots (white) on a pigmented background of hair, feathers or scales. Thus a piebald black and white dog is a black dog with white spots. The animal's skin under the white backgro ...
dromedaries in
Kordofan Kordofan ( ar, كردفان ') is a former province of central Sudan. In 1994 it was divided into three new federal states: North Kordofan, South Kordofan and West Kordofan. In August 2005, West Kordofan State was abolished and its territory ...
and Darfur in Sudan. Piebald coloration in some camels is thought to be caused by the ''KITW1'' allele of the KIT gene, though there is likely at least one other mutation that also causes white spotting. The hair is long and concentrated on the throat, shoulders and the hump. The large eyes are protected by prominent supraorbital ridges; the ears are small and rounded. The hump is at least high. The dromedary has long, powerful legs with two toes on each foot. The feet resemble flat, leathery pads. Like the giraffe, dromedaries moves both legs on one side of the body at the same time. Compared with the Bactrian camel, the dromedary has a lighter build, longer limbs, shorter hairs, a harder palate and an insignificant or absent ethmoidal fissure. Unlike the camelids of the genus ''Lama'', the dromedary has a hump, and in comparison has a longer tail, smaller ears, squarer feet, and a greater height at the shoulder. The dromedary has four teats instead of the two in the ''Lama'' species.


Anatomy

The cranium of the dromedary consists of a postorbital bar, a tympanic bulla filled with spongiosa, a well-defined sagittal crest, a long facial part and an indented nasal bone. Typically, there are eight sternal and four non-sternal pairs of ribs. The spinal cord is nearly long; it terminates in the second and third sacral vertebra. The
fibula The fibula or calf bone is a leg bone on the lateral side of the tibia, to which it is connected above and below. It is the smaller of the two bones and, in proportion to its length, the most slender of all the long bones. Its upper extremity i ...
is reduced to a malleolar bone. The dromedary is a digitigrade animal; it walks on its toes, which are known as digits. It lacks the second and fifth digits. The front feet are wide and long; they are larger than the hind feet, which measure wide and long. The dromedary has 22 milk teeth, which are eventually replaced by 34 permanent teeth. The
dental formula Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiolog ...
for permanent dentition is , and for
milk Milk is a white liquid food produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals (including breastfed human infants) before they are able to digest solid food. Immune factors and immune-modula ...
dentition. In the juvenile, the lower first
molars The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone to ...
develop by 12 to 15 months and the permanent lower
incisor Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wher ...
s appear at 4.5 to 6.5 years of age. All teeth are in use by 8 years. The lenses of the eyes contain
crystallin In anatomy, a crystallin is a water-soluble structural protein found in the lens and the cornea of the eye accounting for the transparency of the structure. It has also been identified in other places such as the heart, and in aggressive breast c ...
, which constitutes 8 to 13% of the protein present there. The skin is black; the epidermis is thick and the dermis is thick. The hump is composed of fat bound together by
fibrous tissue Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...
. There are no glands on the face; males have glands that appear to be modified apocrine sweat glands that secrete pungent, coffee-coloured fluid during the rut, located on either side of the neck midline. The glands generally grow heavier during the rut, and range from . Each cover hair is associated with an arrector pilli muscle, a hair follicle, a ring of sebaceous glands and a sweat gland. Females have cone-shaped, four-chambered
mammary gland A mammary gland is an exocrine gland in humans and other mammals that produces milk to feed young offspring. Mammals get their name from the Latin word ''mamma'', "breast". The mammary glands are arranged in organs such as the breasts in pri ...
s that are long with a base diameter of . These glands can produce milk with up to 90% water content even if the mother is at risk of dehydration. The heart weighs around ; it has two ventricles with the tip curving to the left. The pulse rate is 50 beats per minute. The dromedary is the only mammal with oval red blood corpuscles, which facilitates blood flow during dehydration. The pH of the blood varies from 7.1 to 7.6 (slightly alkaline). The individual's state of hydration and sex and the time of year can influence blood values. The lungs lack lobes. A dehydrated camel has a lower breathing rate. Each kidney has a capacity of , and can produce urine with high
chloride The chloride ion is the anion (negatively charged ion) Cl−. It is formed when the element chlorine (a halogen) gains an electron or when a compound such as hydrogen chloride is dissolved in water or other polar solvents. Chloride sa ...
concentrations. Like the horse, the dromedary has no
gall bladder In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath the liver, although ...
. The grayish violet, crescent-like spleen weighs less than . The triangular, four-chambered liver weighs ; its dimensions are .


Reproductive system

The
ovaries The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. T ...
are reddish, circular and flattened. They are enclosed in a conical bursa and have the dimensions during anestrus. The
oviduct The oviduct in mammals, is the passageway from an ovary. In human females this is more usually known as the Fallopian tube or uterine tube. The eggs travel along the oviduct. These eggs will either be fertilized by spermatozoa to become a zygote, o ...
s are long. The
uterus The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The ...
is bicornuate. The
vagina In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...
is long and has well-developed Bartholin's glands. The
vulva The vulva (plural: vulvas or vulvae; derived from Latin for wrapper or covering) consists of the external female sex organs. The vulva includes the mons pubis (or mons veneris), labia majora, labia minora, clitoris, vestibular bulbs, vulv ...
is deep and has a small clitoris. The placenta is diffuse and epitheliochorial, with a crescent-like
chorion The chorion is the outermost fetal membrane around the embryo in mammals, birds and reptiles (amniotes). It develops from an outer fold on the surface of the yolk sac, which lies outside the zona pellucida (in mammals), known as the vitell ...
. The
penis A penis (plural ''penises'' or ''penes'' () is the primary sexual organ that male animals use to inseminate females (or hermaphrodites) during copulation. Such organs occur in many animals, both vertebrate and invertebrate, but males d ...
is covered by a triangular
penile sheath Almost all mammal penises have foreskins or prepuce, although in non-human cases the foreskin is usually a sheath (sometimes called the ''preputial sheath'', ''praeputium'' or ''penile sheath'') into which the whole penis is retracted. In koalas ...
that opens backwards; it is about long. The
scrotum The scrotum or scrotal sac is an anatomical male reproductive structure located at the base of the penis that consists of a suspended dual-chambered sac of skin and smooth muscle. It is present in most terrestrial male mammals. The scrotum co ...
is located high in the
perineum The perineum in humans is the space between the anus and scrotum in the male, or between the anus and the vulva in the female. The perineum is the region of the body between the pubic symphysis (pubic arch) and the coccyx (tail bone), includi ...
with the testicles in separate sacs. Testicles are long, deep and wide. The right testicle is often smaller than the left. The typical mass of either testicle is less than ; during the rut the mass increases from . The Cowper's gland is white, almond-shaped and lacks
seminal vesicles The seminal vesicles (also called vesicular glands, or seminal glands) are a pair of two convoluted tubular glands that lie behind the urinary bladder of some male mammals. They secrete fluid that partly composes the semen. The vesicles are 5� ...
; the prostate gland is dark yellow, disc-shaped and divided into two lobes. The camel epididymis interstitium revealed several blood vessels harboring special regulatory devices such as the spiral arteries, spiral veins, and throttle arterioles.


Health and diseases

The dromedary generally suffers from fewer diseases than other domestic livestock such as goats and cattle. Temperature fluctuations occur throughout the day in a healthy dromedary – the temperature falls to its minimum at dawn, rises until sunset and falls during the night. Nervous camels may vomit if they are carelessly handled; this does not always indicate a disorder. Rutting males may develop nausea. The dromedary is prone to
trypanosomiasis Trypanosomiasis or trypanosomosis is the name of several diseases in vertebrates caused by parasitic protozoan trypanosomes of the genus ''Trypanosoma''. In humans this includes African trypanosomiasis and Chagas disease. A number of other diseas ...
, a disease caused by a parasite transmitted by the
tsetse fly Tsetse ( , or ) (sometimes spelled tzetze; also known as tik-tik flies), are large, biting flies that inhabit much of tropical Africa. Tsetse flies include all the species in the genus ''Glossina'', which are placed in their own family, Glos ...
. The main symptoms are recurring fever, anaemia and weakness; the disease is typically fatal for the camel.
Brucellosis Brucellosis is a highly contagious zoonosis caused by ingestion of unpasteurized milk or undercooked meat from infected animals, or close contact with their secretions. It is also known as undulant fever, Malta fever, and Mediterranean fever. The ...
is another prominent malady. In an observational study, the
seroprevalence Seroprevalence is the number of persons in a population who test positive for a specific disease based on serology (blood serum) specimens; often presented as a percent of the total specimens tested or as a proportion per 100,000 persons tested. As ...
of this disease was generally low (2 to 5%) in nomadic or moderately free dromedaries, but it was higher (8 to 15%) in denser populations. Brucellosis is caused by different biotypes of ''
Brucella abortus ''Brucella abortus'' is a Gram-negative bacterium in the family Brucellaceae and is one of the causative agents of brucellosis. The rod-shaped pathogen is classified under the domain Bacteria. The prokaryotic ''B. abortus'' is non-spore-forming, ...
'' and '' B. melitensis''. Other internal parasites include '' Fasciola gigantica'' (
trematode Trematoda is a class of flatworms known as flukes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive h ...
), two types of cestode (tapeworm) and various nematodes (roundworms). Among external parasites, ''
Sarcoptes ''Sarcoptes'' is a genus of mites. In some contexts, the types are all considered subordinate to ''Sarcoptes scabiei ''Sarcoptes scabiei'' or the itch mite is a parasitic mite that burrows into skin and causes scabies. The mite is found ...
'' species cause
sarcoptic mange Mange is a type of skin disease caused by parasitic mites. Because various species of mites also infect plants, birds and reptiles, the term "mange", or colloquially "the mange", suggesting poor condition of the skin and fur due to the infection ...
. In a 2000 study in
Jordan Jordan ( ar, الأردن; tr. ' ), officially the Hashemite Kingdom of Jordan,; tr. ' is a country in Western Asia. It is situated at the crossroads of Asia, Africa, and Europe, within the Levant region, on the East Bank of the Jordan Rive ...
, 83% of the 32 camels studied tested positive for sarcoptic mange. In another study, dromedaries were found to have natural antibodies against the rinderpest and ovine rinderpest viruses. In 2013, a seroepidemiological study (a study investigating the patterns, causes and effects of a disease on a specific population on the basis of
serologic Serology is the scientific study of serum and other body fluids. In practice, the term usually refers to the diagnostic identification of antibodies in the serum. Such antibodies are typically formed in response to an infection (against a given mic ...
tests) in Egypt was the first to show the dromedary might be a host for the
Middle East respiratory syndrome coronavirus ''Middle East respiratory syndrome–related coronavirus'' (''MERS-CoV''), or EMC/2012 ( HCoV-EMC/2012), is the virus that causes Middle East respiratory syndrome (MERS). It is a species of coronavirus which infects humans, bats, and camels. Th ...
(MERS-CoV). A 2013–14 study of dromedaries in Saudi Arabia concluded the unusual genetic stability of MERS-CoV coupled with its high seroprevalence in the dromedary makes this camel a highly probable host for the virus. The full genome sequence of MERS-CoV from dromedaries in this study showed a 99.9% match to the genomes of human clade B MERS-CoV. Another study in Saudi Arabia showed the presence of MERS-CoV in 90% of the evaluated dromedaries and suggested that camels could be the animal source of MERS-CoV. Fleas and ticks are common causes of physical irritation. '' Hyalomma dromedarii'' is especially adapted to arid conditions, changing its moulting process to complete more or all of its life cycle on a single host if stressed, and having an unusually wide host range. The larvae are not well understood but their questing phase is assumed to occur during the winter, which is also when rain arrives. The nymphs infest the host mostly in January, then the adults May to September. In a study in Egypt, ''H. dromedarii'' was dominant in dromedaries, comprising 95.6% of the adult ticks isolated from the camels. In Israel, the number of ticks per camel ranged from 20 to 105. Nine camels in the date palm plantations in
Arava Valley The Arabah, Araba or Aravah ( he, הָעֲרָבָה, ''hāʿĂrāḇā''; ar, وادي عربة, ''Wādī ʿAraba''; lit. "desolate and dry area") is a loosely defined geographic area south of the Dead Sea basin, which forms part of the borde ...
were injected with
ivermectin Ivermectin (, '' EYE-vər-MEK-tin'') is an antiparasitic drug. After its discovery in 1975, its first uses were in veterinary medicine to prevent and treat heartworm and acariasis. Approved for human use in 1987, today it is used to treat i ...
, which is not effective against ''Hyalomma'' tick infestations. Larvae of the camel nasal fly '' Cephalopsis titillator'' can cause possibly fatal
brain compression Brain herniation is a potentially deadly side effect of very high pressure within the skull that occurs when a part of the brain is squeezed across structures within the skull. The brain can shift across such structures as the falx cerebri, the te ...
and nervous disorders. Illnesses that can affect dromedary productivity are
pyogenic Pus is an exudate, typically white-yellow, yellow, or yellow-brown, formed at the site of inflammation during bacterial or fungal infection. An accumulation of pus in an enclosed tissue space is known as an abscess, whereas a visible collection ...
diseases and wound infections caused by '' Corynebacterium'' and ''
Streptococcus ''Streptococcus'' is a genus of gram-positive ' (plural ) or spherical bacteria that belongs to the family Streptococcaceae, within the order Lactobacillales (lactic acid bacteria), in the phylum Bacillota. Cell division in streptococci occurs ...
'', pulmonary disorders caused by ''
Pasteurella __NOTOC__ ''Pasteurella'' is a genus of Gram-negative, facultatively anaerobic bacteria. ''Pasteurella'' species are nonmotile and pleomorphic, and often exhibit bipolar staining ("safety pin" appearance). Most species are catalase- and oxidase ...
'' such as hemorrhagic septicemia and '' Rickettsia'' species,
camelpox Camelpox is a disease of camels caused by the camelpox virus (CMPV) of the family ''Poxviridae'', subfamily ''Chordopoxvirinae'', and the genus ''Orthopoxvirus''. It causes skin lesions and a generalized infection. Approximately 25% of young ca ...
, anthrax, and
cutaneous Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different d ...
necrosis caused by '' Streptothrix'' and deficiency of salt in the diet.


Ecology

The dromedary is diurnal (active mainly during daylight); free-ranging herds feed and roam throughout the day, though they rest during the hottest hours around noon. The night is mainly spent resting. Dromedaries form cohesive groups of about 20 individuals, which consist of several females led by a dominant male. Females may also lead in turns. Some males either form bachelor groups or roam alone. Herds may congregate to form associations of hundreds of camels during migrations at the time of natural disasters. The males of the herd prevent female members from interacting with bachelor males by standing or walking between them and sometimes driving the bachelor males away. In Australia, short-term
home range A home range is the area in which an animal lives and moves on a periodic basis. It is related to the concept of an animal's territory which is the area that is actively defended. The concept of a home range was introduced by W. H. Burt in 1943. He ...
s of feral dromedaries cover ; annual home ranges can spread over several thousand square kilometres. Special behavioral features of the dromedary include snapping at others without biting them and showing displeasure by stamping their feet. They are generally non-aggressive, with the exception of rutting males. They appear to remember their homes; females, in particular, remember the places they first gave birth or suckled their offspring. Males become aggressive in the mating season, and sometimes wrestle. A 1980 study showed
androgen An androgen (from Greek ''andr-'', the stem of the word meaning "man") is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This in ...
levels in males influences their behavior. Between January and April when these levels are high during the rut, they become difficult to manage, blow out the palate from the mouth, vocalize and throw urine over their backs. Camels scratch parts of their bodies with their legs or with their lower incisors. They may also rub against tree bark and roll in the sand. Free-ranging dromedaries face large predators typical of their regional distribution, which includes
wolves The wolf (''Canis lupus''; : wolves), also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of ''Canis lupus'' have been recognized, and gray wolves, as popularly un ...
, lions and tigers.


Diet

The dromedary's diet consists mostly of foliage, dry grasses and desert vegetation – mostly thorny plants. A study said the typical diet of the dromedary is dwarf shrubs (47.5%), trees (29.9%), grasses (11.2%), other herbs (0.2%) and vines (11%). The dromedary is primarily a browser;
forb A forb or phorb is an herbaceous flowering plant that is not a graminoid (grass, sedge, or rush). The term is used in biology and in vegetation ecology, especially in relation to grasslands and understory. Typically these are dicots without woo ...
s and shrubs comprise 70% of its diet in summer and 90% of its diet in winter. The dromedary may also graze on tall, young, succulent grasses. In the Sahara, 332 plant species have been recorded as food plants of the dromedary. These include '' Aristida pungens'', ''
Acacia tortilis ''Vachellia tortilis'', widely known as ''Acacia tortilis'' but now attributed to the genus '' Vachellia'', is the umbrella thorn acacia, also known as ''umbrella thorn'' and Israeli babool, a medium to large canopied tree native to most of Afr ...
'', ''
Panicum turgidum ''Panicum turgidum'' is an old world clumping desert bunchgrass of the genus '' Panicum''. It is a plant of arid regions across Africa and Asia, and has been introduced to other parts of the world. Description ''Panicum turgidum'' is a perennia ...
'', '' Launaea arborescens'' and ''
Balanites aegyptiaca ''Balanites aegyptiaca'' (also known as the Egyptian balsam) is a species of tree, classified as a member of either the Zygophyllaceae or the Balanitaceae. This tree is native to much of Africa and parts of the Middle East. There are many comm ...
''. The dromedary eats '' Acacia'', '' Atriplex'' and ''
Salsola ''Salsola'' is a genus of the subfamily Salsoloideae in the family Amaranthaceae. The genus ''sensu stricto'' is distributed in central and southwestern Asia, North Africa, and the Mediterranean. A common name of various members of this genus and ...
'' when they are available. Feral dromedaries in Australia prefer '' Trichodesma zeylanicum'' and '' Euphorbia tannensis''. In India, dromedaries are fed with forage plants such as '' Vigna aconitifolia'', '' V. mungo'', '' Cyamopsis tetragonolaba'', '' Melilotus parviflora'', '' Eruca sativa'', '' Trifolium'' species and '' Brassica campestris''. Dromedaries keep their mouths open while chewing thorny food. They use their lips to grasp the food and chew each bite 40 to 50 times. Its long eyelashes, eyebrows, lockable nostrils, caudal opening of the prepuce and a relatively small vulva help the camel avoid injuries, especially while feeding. They graze for 8–12 hours per day and ruminate for an equal amount of time.


Biology


Adaptations

The dromedary is specially adapted to its desert habitat; these adaptations are aimed at conserving water and regulating body temperature. The bushy eyebrows and the double row of eyelashes prevent sand and dust from entering the eyes during strong windstorms, and shield them from the sun's glare. The dromedary is able to close its nostrils voluntarily; this assists in water conservation. The dromedary can conserve water by reducing perspiration by fluctuating the body temperature throughout the day from . The kidneys are specialized to minimize water loss through excretion. Groups of camels avoid excess heat from the environment by pressing against each other. The dromedary can tolerate greater than 30% water loss, which is generally impossible for other mammals. In temperatures between , it needs water every 10 to 15 days. In the hottest temperatures, the dromedary takes water every four to seven days. This camel has a quick rate of rehydration and can drink at per minute. The dromedary has a rete mirabile, a complex of arteries and veins lying very close to each other which uses countercurrent blood flow to cool blood flowing to the brain. This effectively controls the temperature of the brain. The hump stores up to of fat, which the camel can break down into energy to meet its needs when resources are scarce; the hump also helps dissipate body heat. When this tissue is metabolized, through fat metabolization, it releases energy while causing water to evaporate from the lungs during
respiration Respiration may refer to: Biology * Cellular respiration, the process in which nutrients are converted into useful energy in a cell ** Anaerobic respiration, cellular respiration without oxygen ** Maintenance respiration, the amount of cellul ...
(as oxygen is required for the metabolic process): overall, there is a net decrease in water. If the hump is small, the animal can show signs of starvation. In a 2005 study, the mean volume of adipose tissues (in the external part of the hump that have cells to store lipids) is related to the dromedary's unique mechanism of food and water storage. In case of starvation, they can even eat fish and bones, and drink brackish and salty water. The hair is longer on the throat, hump and shoulders. Though the padded hooves effectively support the camel's weight on the ground, they are not suitable for walking on slippery and muddy surfaces.


Reproduction

Camels have a slow growth rate and reach sexual maturity slower than sheep or goat. The age of sexual maturity varies geographically and depends on the individual, as does the reproductive period. Both sexes might mature by three to five years of age, though successful breeding could take longer. Camels are described as atypical seasonal breeders; they exhibit spermatogenesis throughout the whole year with a reduction in spermatogenesis during the nonbreeding season compared to that in the breeding season (Zayed et al., 1995). The breeding season in Egypt is during spring; the spring months. Mating occurs once a year, and peaks in the rainy season. The mating season lasts three to five months, but may last a year for older animals. During the reproductive season, males splash their urine on their tails and nether regions. To attract females they extrude their soft palate – a trait unique to the dromedary. As the male gurgles, copious quantities of saliva turns to foam and covers the mouth. Males threaten each other for dominance over the female by trying to stand taller than the other, making low noises and a series of head movements including lowering, lifting and bending their necks backward. Males try to defeat other males by biting the opponent's legs and taking the head between his jaws. Copulation begins with foreplay; the male smells the female's genitalia and often bites her there or around her hump. The male forces the female to sit, then grasps her with his forelegs. Camelmen often aid the male insert his penis into the female's vulva. The male dromedary's ability to penetrate the female on his own is disputed, though feral populations in Australia reproduce naturally. Copulation takes from 7 to 35 minutes, averaging 11 to 15 minutes. Normally, three to four ejaculations occur. The
semen Semen, also known as seminal fluid, is an organic bodily fluid created to contain spermatozoa. It is secreted by the gonads (sexual glands) and other sexual organs of male or hermaphroditic animals and can fertilize the female ovum. Sem ...
of a Bikaneri dromedary is white and viscous, with a pH of around 7.8. A single calf is born after a gestation period of 15 months. Calves move freely by the end of their first day. Nursing and maternal care continue for one to two years. In a study to find whether young could exist on milk substitutes, two male, month-old camels were separated from their mothers and were fed on milk substitutes prepared commercially for lambs, and they grew to normal weights for male calves after 30 days. Lactational yield can vary with species, breed, individual, region, diet, management conditions and lactating stage. The largest quantity of milk is produced during the early period of lactation. The lactation period can vary between nine and eighteen months. Dromedaries are induced ovulators. Oestrus may be cued by the nutritional status of the camel and the length of day. If mating does not occur, the follicle, which grows during oestrus, usually regresses within a few days. In one study, 35 complete oestrous cycles were observed in five nonpregnant females over 15 months. The cycles were about 28 days long; follicles matured in six days, maintained their size for 13 days, and returned to their original size in eight days. In another study, ovulation could be best induced when the follicle reaches a size of . In another study, pregnancy in females could be recognized as early as 40 to 45 days of gestation by the swelling of the left
uterine horn The uterine horns (cornua of uterus) are the points in the upper uterus where the fallopian tubes exit to meet the ovaries. They are one of the points of attachment for the round ligament of uterus (the other being the mons pubis). They also provi ...
, where 99.5% of pregnancies were located.


Range

Its range included hot, arid regions of northern Africa, Ethiopia, the Near East, and western and central Asia. The dromedary typically thrives in areas with a long dry season and a short wet season. They are sensitive to cold and humidity, though some breeds can thrive in humid conditions. The dromedary may have been first domesticated in Somalia or the Arabian Peninsula about 4,000 years ago. In the ninth or tenth century BC, the dromedary became popular in the Near East. The Persian invasion of Egypt under
Cambyses Cambyses may refer to: * Cambyses I, King of Anshan 600 to 559 BCE * Cambyses II, King of Persia 530 to 522 BCE * Cambyses, ancient name of the Iori river in the South Caucasus * ''Cambyses'', a tragedy (published 1569) by Thomas Preston (writer) ...
in 525 BC introduced domesticated camels to the area. The Persian camels were not well-suited to trading or travel over the Sahara; journeys across the desert were made on chariots pulled by horses. The dromedary was introduced into Egypt from south-western Asia (Arabia and Persia). The popularity of dromedaries increased after the Islamic conquest of North Africa. While the invasion was accomplished largely on horseback, new links to the Middle East allowed camels to be imported ''en masse''. These camels were well-suited to long desert journeys and could carry a great deal of cargo, allowing substantial trans-Saharan trade for the first time. In Libya, dromedaries were used for transport and their milk and meat constituted the local diet. Dromedaries were also shipped from south-western Asia to Spain, Italy, Turkey, France, Canary Islands, the Americas and Australia. Dromedaries were introduced into Spain in 1020 AD and to
Sicily (man) it, Siciliana (woman) , population_note = , population_blank1_title = , population_blank1 = , demographics_type1 = Ethnicity , demographics1_footnotes = , demographi ...
in 1059 AD. Camels were exported to the Canary Islands in 1405 during the European colonisation of the area, and are still extant there, especially in Lanzarote and to the south of Fuerteventura. Attempts to introduce dromedaries into the Caribbean, Colombia, Peru, Bolivia and Brazil were made between the 17th and 19th centuries; some were imported to the western United States in the 1850s and some to Namibia in the early 1900s, but presently they exist in small numbers or are absent in these areas. In 1840, about six camels were shipped from Tenerife to
Adelaide Adelaide ( ) is the capital city of South Australia, the state's largest city and the fifth-most populous city in Australia. "Adelaide" may refer to either Greater Adelaide (including the Adelaide Hills) or the Adelaide city centre. The dem ...
, but only one survived the journey to arrive on 12 October that year. The animal, a male called Harry, was owned by the explorer
John Ainsworth Horrocks John Ainsworth Horrocks (22 March 1818 – 23 September 1846) was an English pastoralist and explorer who was one of the first European settlers in the Clare Valley of South Australia where, in 1840, he established the village of Penwortham. ...
. Harry was ill-tempered but was included in an expedition the following year because he could carry heavy loads. The next major group of camels were imported into Australia in 1860, and between 1860 and 1907 10 to 12 thousand were imported. These were used mainly for riding and transport.


Current distribution of captive animals

In the early 21st century, the domesticated dromedary is found in the semi-arid to arid regions of the Old World.


Africa

Africa has more than 80% of the world's total dromedary population; it occurs in almost every desert zone in the northern part of the continent. The Sahel marks the southern extreme of its range, where the annual rainfall is around . The Horn of Africa has nearly 35% of the world's dromedaries; most of the region's stock is in
Somalia Somalia, , Osmanya script: 𐒈𐒝𐒑𐒛𐒐𐒘𐒕𐒖; ar, الصومال, aṣ-Ṣūmāl officially the Federal Republic of SomaliaThe ''Federal Republic of Somalia'' is the country's name per Article 1 of thProvisional Constituti ...
, followed by Sudan, Eritrea, and
Ethiopia Ethiopia, , om, Itiyoophiyaa, so, Itoobiya, ti, ኢትዮጵያ, Ítiyop'iya, aa, Itiyoppiya officially the Federal Democratic Republic of Ethiopia, is a landlocked country in the Horn of Africa. It shares borders with Eritrea to the ...
(as of the early 2000s). According to the Yearbook of the
Food and Agriculture Organization The Food and Agriculture Organization of the United Nations (FAO)french: link=no, Organisation des Nations unies pour l'alimentation et l'agriculture; it, Organizzazione delle Nazioni Unite per l'Alimentazione e l'Agricoltura is an intern ...
(FAO) for 1984, eastern Africa had about 10 million dromedaries, the largest population of Africa. Western Africa followed with 2.14 million, while northern Africa had nearly 0.76 million. Populations in Africa increased by 16% from 1994 to 2005.


Asia

In Asia, nearly 70% of the population occurs in India and Pakistan. The combined population of the dromedary and the Bactrian camel decreased by around 21% between 1994 and 2004. The dromedary is sympatric with the Bactrian camel in Afghanistan, Pakistan, and central and southwestern Asia. India has a dromedary population of less than one million, with most (0.67 million) in the state of
Rajasthan Rajasthan (; lit. 'Land of Kings') is a state in northern India. It covers or 10.4 per cent of India's total geographical area. It is the largest Indian state by area and the seventh largest by population. It is on India's northwestern s ...
. Populations in Pakistan decreased from 1.1 million in 1994 to 0.8 million in 2005 – a 29% decline. According to the FAO, the dromedary population in six countries of the
Persian Gulf The Persian Gulf ( fa, خلیج فارس, translit=xalij-e fârs, lit=Gulf of Fars, ), sometimes called the ( ar, اَلْخَلِيْجُ ٱلْعَرَبِيُّ, Al-Khalīj al-ˁArabī), is a mediterranean sea in Western Asia. The bod ...
was nearly 0.67 million in 2003. In the Persian Gulf region the dromedary is locally classified into breeds including Al-Majahem, Al-Hamrah, Al-Safrah, Al-Zarkah and Al-Shakha, based on coat colour. The UAE has three prominent breeds: Racing camel, Al-Arabiat and Al-Kazmiat.


Feral population

Feral dromedary populations occur in Australia, where they were introduced in 1840. The total dromedary population in Australia was 500,000 in 2005. Nearly 99% of the populations are feral, and they have annual growth rate of 10%. Most of the Australian feral camels are dromedaries, with only a few Bactrian camels. Most of the dromedaries occur in
Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...
, with smaller populations in the
Northern Territory The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an Australian territory in the central and central northern regions of Australia. The Northern Territory shares its borders with Western Aust ...
,
Western Queensland Western Queensland encompasses the three western regions in the Australian state of Queensland: * North West Queensland, often known as Gulf Country; * Central West Queensland; and * South West Queensland. History Karuwali (also known as '' ...
and northern
South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
.


Relationship with humans

The strength and docility of the dromedary make it popular as a domesticated animal. According to
Richard Bulliet Richard W. Bulliet (born 1940) is a professor of history at Columbia University who specializes in the history of Islamic society and institutions, the history of technology, and the history of the role of animals in human society. Early life ...
, they can be used for a wide variety of purposes: riding, transport, ploughing, and trading and as a source of milk, meat, wool and leather. The main attraction of the dromedary for nomadic desert-dwellers is the wide variety of resources they provide, which are crucial for their survival. It is important for several Bedouin pastoralist tribes of northern
Arabia The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plat ...
, such as the
Ruwallah The Ruwallah ( ar, الرولة, singular Ruweili/Ruwaili) are a large Arab tribe of northern Arabia and the Syrian Desert, including modern-day Jordan. History Until the demarcation of borders in the Middle East in the early 20th century, the Ruw ...
, the Rashaida, the Bani Sakhr and the
Mutayr Mutayr () is an Arab tribe that originated in the northern Hejaz near Medina. The tribe mainly inhabits Saudi Arabia (Najd), Kuwait, Iraq, Morocco, and Tunisia. Genealogy Ahmad al-Qalqashandi who died in 1418 stated that al-Mutayr tribe belongs ...
. Camel urine and camel milk is used for
medicinal purposes ''Medicinal Purposes'' is a Big Finish Productions audio drama based on the long-running British science fiction television series ''Doctor Who''. Plot Edinburgh, 1827. Body snatchers William Burke and William Hare are on the loose while the ...
.


Riding camels

Although the role of the camel is diminishing with the advent of technology and modern means of transport, it is still an efficient mode of communication in remote and less-developed areas. The dromedary has been used in warfare since the 2nd century BC. It is particularly prized for its capability to outrun horses in the deserts. Record of its use during the time of
Alexander the Great Alexander III of Macedon ( grc, Ἀλέξανδρος, Alexandros; 20/21 July 356 BC – 10/11 June 323 BC), commonly known as Alexander the Great, was a king of the ancient Greek kingdom of Macedon. He succeeded his father Philip II to ...
indicate that the animal could cover up to 50 miles per day for a week and they could go for up to a month without water. An account by Aurelian also cited that, in her escape to
Euphrates The Euphrates () is the longest and one of the most historically important rivers of Western Asia. Together with the Tigris, it is one of the two defining rivers of Mesopotamia ( ''the land between the rivers''). Originating in Turkey, the Eup ...
, Zenobia used a dromedary to outrun her pursuers after she was defeated at
Palmyra Palmyra (; Palmyrene: () ''Tadmor''; ar, تَدْمُر ''Tadmur'') is an ancient city in present-day Homs Governorate, Syria. Archaeological finds date back to the Neolithic period, and documents first mention the city in the early secon ...
. The dromedary also remains popular for racing, particularly in the
Arab world The Arab world ( ar, اَلْعَالَمُ الْعَرَبِيُّ '), formally the Arab homeland ( '), also known as the Arab nation ( '), the Arabsphere, or the Arab states, refers to a vast group of countries, mainly located in Western A ...
. Riding camels of Arabia, Egypt and the Sahara are locally known as the Dilool, the Hageen, and the Mehara respectively; several local breeds are included within these groups. The ideal riding camel is strong, slender and long-legged with thin, supple skin. The special adaptations of the dromedary's feet allow it to walk with ease on sandy and rough terrain and on cold surfaces. The camels of the Bejas of Sudan and the Hedareb, Bilen, and the Tigre people of Eritrea and the Anafi camel bred in Sudan are common breeds used as riding camels. According to Leese, the dromedary walks with four speeds or gaits: walk, jog, fast run and canter. The first is the typical speed of walking, around . Jog is the most common speed, nearly on level ground. He estimated a speed of during a fast run, by observing northern African and Arabian dromedaries. He gave no speed range to describe the canter, but implied it was a type of gallop that if induced could exhaust the camel and the rider. Canter could be used only for short periods of time, for example in races. The ideal age to start training dromedaries for riding is three years, although they may be stubborn and unruly. At first the camel's head is controlled, and it is later trained to respond to sitting and standing commands, and to allow mounting. At this stage a camel will often try to escape when a trainer tries to mount it. The next stage involves training it to respond to reins. The animal must be given loads gradually and not forced to carry heavy loads before the age of six. Riding camels should not be struck on their necks, rather they should be struck behind the right leg of the rider. Leese described two types of saddles generally used in camel riding: the Arabian ''markloofa'' used by single riders and the Indian ''pakra'' used when two riders mount the same camel.


Baggage and draught camels

The baggage camel should be robust and heavy. Studies have recommended the camel should have either a small or a large head with a narrow
aquiline nose An aquiline nose (also called a Roman nose) is a human nose with a prominent bridge, giving it the appearance of being curved or slightly bent. The word ''aquiline'' comes from the Latin word ''aquilinus'' ("eagle-like"), an allusion to the curve ...
, prominent eyes and large lips. The neck should be medium to long so the head is held high. The chest should be deep and the hump should be well-developed with sufficient space behind it to accommodate the saddle. The hindlegs should be heavy, muscular and sturdy. The dromedary can be trained to carry baggage from the age of five years, but must not be given heavy loads before the age of six. The ''hawia'' is a typical baggage saddle from Sudan. The methods of training the baggage camels are similar to those for riding camels. Draught camels are used for several purposes including ploughing, processing in oil mills and pulling carts. There is no clear description for the ideal draught camel, though its strength, its ability to survive without water and the flatness of its feet could be indicators. It may be used for ploughing in pairs or in groups with buffaloes or bullocks. The draught camel can plough at around , and should not be used for more than six hours a day – four hours in the morning and two in the afternoon. The camel is not easily exhausted unless diseased or undernourished, and has remarkable endurance and hardiness.


Dairy products

Camel milk is a staple food of nomadic tribes living in deserts. It consists of 11.7% solids, 3% protein, 3.6% fat, 0.8% ash, 4.4% lactose and 0.13% acidity ( pH 6.5). The quantities of sodium, potassium, zinc, iron, copper, manganese, niacin and
vitamin C Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) ...
were relatively higher than the amounts in cow milk. However, the levels of
thiamin Thiamine, also known as thiamin and vitamin B1, is a vitamin, an essential micronutrient, that cannot be made in the body. It is found in food and commercially synthesized to be a dietary supplement or medication. Phosphorylated forms of t ...
, riboflavin,
folacin Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and ...
, vitamin B12,
pantothenic acid Pantothenic acid, also called vitamin B5 is a water-soluble B vitamin and therefore an essential nutrient. All animals require pantothenic acid in order to synthesize coenzyme A (CoA) – essential for fatty acid metabolism – as well as to, ...
,
vitamin A Vitamin A is a fat-soluble vitamin and an essential nutrient for humans. It is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids (most notably ...
, lysine, and tryptophan were lower than those in cow milk. The molar percentages of the
fatty acid In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, ...
s in milk fat were 26.7% for
palmitic acid Palmitic acid (hexadecanoic acid in IUPAC nomenclature) is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The L ...
, 25.5%
oleic acid Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish. In chemical terms, oleic acid is classified as a monounsaturated omeg ...
, 11.4%
myristic acid Myristic acid (IUPAC name: tetradecanoic acid) is a common saturated fatty acid with the molecular formula CH3(CH2)12COOH. Its salts and esters are commonly referred to as myristates or tetradecanoates. It is named after the binomial name for nut ...
and 11% palmitoleic acid. Camel milk has higher thermal stability compared with cow milk, but it does not compare favourably with sheep milk. Daily milk yield generally varies from and from 1.3% to 7.8% of the body weight. Milk yield varies geographically and depends upon the animals' diet and living conditions. At the peak of lactation, a healthy female would typically provide milk per day. Leese estimated a lactating female would yield besides the amount ingested by the calf. The Pakistani dromedary, which is considered a better milker and bigger, can yield when well-fed. Dromedaries in Somalia may be milked between two and four times a day, while those in Afar, Ethiopia, may be milked up to seven times a day. The acidity of dromedary milk stored at increases at a slower rate than that of cow milk. Though the preparation of butter from dromedary milk is difficult, it is produced in small amounts by nomads, optimized at 22.5% fat in the cream. In 2001, the ability of dromedary milk to form curd was studied; coagulation did not show curd formation, and had a pH of 4.4. It was much different from curd produced from cow milk, and had a fragile, heterogeneous composition probably composed of
casein Casein ( , from Latin ''caseus'' "cheese") is a family of related phosphoproteins ( αS1, aS2, β, κ) that are commonly found in mammalian milk, comprising about 80% of the proteins in cow's milk and between 20% and 60% of the proteins in hum ...
flakes. Nevertheless, cheese and other dairy products can be made from camel milk. A study found bovine calf rennet could be used to coagulate dromedary milk. A special factory has been set up in
Nouakchott , image_skyline = Nouakchott.jpg , image_caption = City view of Nouakchott , pushpin_map = Mauritania#Arab world#Africa , pushpin_relief = 1 , mapsize = , map_caption ...
to pasteurise and make cheese from camel milk. Mystical beliefs surround the use of camel milk in some places; for example, it may be used as an aphrodisiac in Ethiopia.


Meat

The meat of a five-year-old dromedary has a typical composition of 76% water, 22% protein, 1% fat, and 1% ash. The carcass, weighing for a five-year-old dromedary, is composed of nearly 57% muscle, 26% bone and 17% fat. A seven-to-eight-year-old camel can produce a carcass of . The meat is bright red to a dark brown or maroon, while the fat is white. It has the taste and texture of beef. A study of the meat of Iranian dromedaries showed its high glycogen content, which makes it taste sweet like horse meat. The carcasses of well-fed camels were found to be covered with a thin layer of good quality fat. In a study of the fatty acid composition of raw meat taken from the hind legs of seven one-to-three years old males, 51.5% of the fatty acids were saturated, 29.9% mono-unsaturated, and 18.6% polyunsaturated. The major fatty acids in the meat were palmitic acid (26.0%), oleic acid (18.9%) and
linoleic acid Linoleic acid (LA) is an organic compound with the formula COOH(CH2)7CH=CHCH2CH=CH(CH2)4CH3. Both alkene groups are ''cis''. It is a fatty acid sometimes denoted 18:2 (n-6) or 18:2 ''cis''-9,12. A linoleate is a salt or ester of this acid. ...
(12.1%). In the hump, palmitic acid was dominant (34.4%), followed by oleic acid (28.2%), myristic acid (10.3%) and stearic acid (10%). Dromedary slaughter is more difficult than the slaughter of other domestic livestock such as cattle because of the size of the animal and the significant manual work involved. More males than females are slaughtered. Though less affected by mishandling than other livestock, the pre-slaughter handling of the dromedary plays a crucial role in determining the quality of meat obtained; mishandling can often disfigure the hump. The animal is stunned, seated in a crouching position with the head in a caudal position and slaughtered. The dressing percentage – the percentage of the mass of the animal that forms the carcass – is 55–70%, more than the 45–50% of cattle. Camel meat is often eaten by African camel herders, who use it only during severe food scarcity or for rituals. Camel meat is processed into food items such as burgers, patties, sausages and ''
shawarma Shawarma (; ar, شاورما) is a popular Middle Eastern dish that originated in the Ottoman Empire, consisting of meat cut into thin slices, stacked in a cone-like shape, and roasted on a slowly-turning vertical rotisserie or spit. Tradition ...
''. Dromedaries can be slaughtered between four and ten years of age. As the animal ages, the meat grows tougher and deteriorates in taste and quality. In Somalian and Djiboutian culture, the dromedary is a staple food and can be found in many recipes and dishes. A 2005 report issued jointly by the
Ministry of Health (Saudi Arabia) The Ministry of Health ( ar, وزارة الصحة), commonly abbreviated to MoH, is the ministry overseeing the health care and health policy of Saudi Arabia. The ministry is tasked with formulating strategies to ensure public health in the cou ...
and the United States
Centers for Disease Control and Prevention The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgi ...
details five cases of bubonic plague in humans resulting from the ingestion of raw camel liver. Four of the five patients had severe pharyngitis and submandibular
lymphadenitis Lymphadenopathy or adenopathy is a disease of the lymph nodes, in which they are abnormal in size or consistency. Lymphadenopathy of an inflammatory type (the most common type) is lymphadenitis, producing swollen or enlarged lymph nodes. In cl ...
. ''
Yersinia pestis ''Yersinia pestis'' (''Y. pestis''; formerly '' Pasteurella pestis'') is a gram-negative, non-motile, coccobacillus bacterium without spores that is related to both ''Yersinia pseudotuberculosis'' and ''Yersinia enterocolitica''. It is a facult ...
'' was isolated from the camel's bone marrow, from the
jird ''Meriones'' is a rodent genus that includes the gerbil most commonly kept as a pet, ''Meriones unguiculatus''. The genus contains most animals referred to as jirds, but members of the genera '' Sekeetamys'', ''Brachiones'', and sometimes '' Pach ...
(''Meriones libycus'') and from fleas (''
Xenopsylla cheopis The Oriental rat flea (''Xenopsylla cheopis''), also known as the tropical rat flea or the rat flea, is a parasite of rodents, primarily of the genus ''Rattus'', and is a primary vector for bubonic plague and murine typhus. This occurs when a fl ...
'') captured at the camel's
corral A pen is an enclosure for holding livestock. It may also perhaps be used as a term for an enclosure for other animals such as pets that are unwanted inside the house. The term describes types of enclosures that may confine one or many animal ...
.


Camel hair, wool and hides

Camels in hot climates generally do not develop long coats. Camel hair is light, and has low
thermal conductivity The thermal conductivity of a material is a measure of its ability to conduct heat. It is commonly denoted by k, \lambda, or \kappa. Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal ...
and durability, and is thus suitable for manufacturing warm clothes, blankets, tents, and rugs. Hair of highest quality is typically obtained from juvenile or wild camels. In India, camels are clipped usually in spring and around hair is produced per clipping. In colder regions one clipping can yield as much as . A dromedary can produce wool per year, whereas a Bactrian camel has an annual yield of nearly . Dromedaries under the age of two years have a fine undercoat that tends to fall off and should be cropped by hand. Little information about camel hides has been collected but they are usually of inferior quality and are less preferred for manufacturing leather.


See also

* Camel urine * List of animals with humps


References


External links

*
Could
Emirati camels hold the key to treating venomous snake bites? {{Authority control Camels Mammals of Africa Mammals of Asia Mammals of Pakistan Fauna of Iran Fauna of the Middle East Fauna of Jordan Fauna of Syria Fauna of Iraq Mammals of the Arabian Peninsula Fauna of the Sahara Mammals of Somalia Livestock Pack animals Mammals described in 1758 Mammals of North Africa Taxa named by Carl Linnaeus Symbols of Rajasthan