| Dromedary | |||
|---|---|---|---|
| |||
| General information | |||
| Universe | Real Life | ||
| Aliases | Dromedary camel Arabian camel | ||
| Classification | Camelus dromedarius | ||
| Species type | Camelid | ||
| Homeworld | Earth | ||
| Environment | Desert | ||
| Intelligence | Non-sapient | ||
| Biochemistry | Carbon-based lifeform | ||
| Biological information | |||
| Lifespan | 40 years | ||
| Reproduction | Sexual, viviparous | ||
| Average height | ♂: 1.8–2 m (5 ft 11 in–6 ft 7 in) at the shoulder ♀: 1.7–1.9 m (5 ft 7 in–6 ft 3 in) at the shoulder | ||
| Average weight | ♂: 400 and 600 kg (880 and 1,320 lb) ♀: 300 and 540 kg (660 and 1,190 lb) | ||
| Average length | 2.19-3.41 m (7'2.4"-11'2.4") | ||
| Locomotion | Quadrupedal | ||
| Feeding behavior | Herbivorous | ||
| Predators | Lions Leopards Humans Wolves Tigers | ||
| Distinctive features | Single hump on back | ||
| Eye color | Black | ||
| Skin color | Black | ||
| Lineage information | |||
| Cultural information | |||
| Sociocultral characteristics | |||
| Scientific taxonomy | |||
| Planet | Earth | ||
| Domain | Eukaryota | ||
| Kingdom | Animalia | ||
| Subkingdom | Eumetazoa | ||
| Infrakingdom | Bilateria | ||
| Superphylum | Deuterostomia | ||
| Phylum | Chordata | ||
| Subphylum | Vertebrata | ||
| Infraphylum | Gnathostomia | ||
| Superclass | Tetrapoda | ||
| Class | Mammalia | ||
| Subclass | Theria (Wild beasts) | ||
| Infraclass | Placentalia (Placental mammals) | ||
| Superorder | Laurasiatheria | ||
| Order | Artiodactyla (Even-toed ungulates) | ||
| Suborder | Tylopoda (Calloused foot ungulates) | ||
| Superfamily | Cameloidea | ||
| Family | Camelidae (Camelids) | ||
| Tribe | Camelini | ||
| Genus | Camelus | ||
| Species | C. dromedarius | ||
| Other information | |||
| Status | Domesticated (New 2022-Current)
Least Concern | ||
| Creator | God (debated) | ||
| Possible population | 15 million | ||
The dromedary (Camelus dromedarius) is the tallest of the 3 species of camel, they can be identified by the single hump on their back.
Characteristics[]
The dromedary is the tallest of the three camel species. Adult males range in height between 1.8 and 2 m (5.9 and 6.6 ft) at the shoulder; females range between 1.7 and 1.9 m (5.6 and 6.2 ft). Males typically weigh between 400 and 600 kg (880 and 1,320 lb); females range between 300 and 540 kg (660 and 1,190 lb). 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 (dulaa in Arabic) nearly 18 cm (7.1 in) long, which it 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 dromedaries in Kordofan 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 20 cm (7.9 in) 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 214 cm (84 in) long; it terminates in the second and third sacral vertebra. The fibula 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 19 cm (7.5 in) wide and 18 cm (7.1 in) long; they are larger than the hind feet, which measure 17 cm (6.7 in) wide and 16 cm (6.3 in) long.
The dromedary has 22 milk teeth, which are eventually replaced by 34 permanent teeth. The dental formula for permanent dentition is 1.1.3.3/3.1.2.3, and 1.1.3/3.1.2 for milk dentition. In the juvenile, the lower first molars develop by 12 to 15 months and the permanent lower incisors 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, which constitutes 8 to 13% of the protein present there.
The skin is black; the epidermis is 0.038–0.064 mm (0.0015–0.0025 in) thick and the dermis is 2.2–4.7 mm (0.087–0.185 in) thick. The hump is composed of fat bound together by fibrous tissue. 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 20 to 115 g (0.71 to 4.06 oz). 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 glands that are 2.4 cm (0.94 in) long with a base diameter of 1.5 cm (0.59 in). These glands can produce milk with up to 90% water content even if the mother is at risk of dehydration.
The heart weighs around 5 kg (11 lb); 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 858 cm3 (52.4 cu in), and can produce urine with high chloride concentrations. Like the horse, the dromedary has no gall bladder. The grayish violet, crescent-like spleen weighs less than 500 g (18 oz). The triangular, four-chambered liver weighs 6.5 kg (14 lb); its dimensions are 60 cm × 42 cm × 18 cm (24 in × 17 in × 7 in).
Reproductive system[]
The ovaries are reddish, circular and flattened. They are enclosed in a conical bursa and have the dimensions 4×2.5×0.5 cm (1.57×0.98×0.20 in) during anestrus. The oviducts are 25–28 cm (9.8–11.0 in) long. The uterus is bicornuate. The vagina is 3–3.5 cm (1.2–1.4 in) long and has well-developed Bartholin's glands. The vulva is 3–5 cm (1.2–2.0 in) deep and has a small clitoris. The placenta is diffuse and epitheliochorial, with a crescent-like chorion.
The penis is covered by a triangular penile sheath that opens backwards; it is about 60 cm (24 in) long. The scrotum is located high in the perineum with the testicles in separate sacs. Testicles are 7–10 cm (2.8–3.9 in) long, 4.5 cm (1.8 in) deep and 5 cm (2.0 in) wide. The right testicle is often smaller than the left. The typical mass of either testicle is less than 140 g (0.31 lb); during the rut the mass increases from 165 to 253 g (0.364 to 0.558 lb). The Cowper's gland is white, almond-shaped and lacks seminal vesicles; 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, a disease caused by a parasite transmitted by the tsetse fly. The main symptoms are recurring fever, anaemia and weakness; the disease is typically fatal for the camel. Brucellosis is another prominent malady. In an observational study, the seroprevalence 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 and B. melitensis. Other internal parasites include Fasciola gigantica (trematode), two types of cestode (tapeworm) and various nematodes (roundworms). Among external parasites, Sarcoptes species cause sarcoptic mange. In a 2000 study in Jordan, 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 tests) in Egypt was the first to show the dromedary might be a host for the Middle East respiratory syndrome coronavirus (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 were injected with ivermectin, which is not effective against Hyalomma tick infestations.[clarification needed] Larvae of the camel nasal fly Cephalopsis titillator can cause possibly fatal brain compression and nervous disorders. Illnesses that can affect dromedary productivity are pyogenic diseases and wound infections caused by Corynebacterium and Streptococcus, pulmonary disorders caused by Pasteurella such as hemorrhagic septicemia and Rickettsia species, camelpox, anthrax, and cutaneous 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 ranges of feral dromedaries cover 50 to 150 km2 (19 to 58 sq mi); 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 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, 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; forbs 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, Panicum turgidum, Launaea arborescens and Balanites aegyptiaca. The dromedary eats Acacia, Atriplex and Salsola 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.