Dung beetle
Dung beetles are beetles that feed or on feces. A dung beetle can bury dung 250 times heavier than itself in one night. Many dung beetles, known as rollers, roll dung into round balls, which are used as a food source or breeding chambers. Others, known as tunnelers, bury the dung. A third group, the dwellers, neither roll nor burrow: they live in manure, they are attracted by the dung collected by burrowing owls. There are dung beetle species of different colours and sizes, some functional traits such as body mass and leg length can have high levels of variability. All the species belong to the superfamily Scarabaeoidea; as most species of Scarabaeinae feed on feces, that subfamily is dubbed true dung beetles. There are dung-feeding beetles, such as the Geotrupidae; the Scarabaeinae alone comprises more than 5,000 species. The nocturnal African dung beetle Scarabaeus satyrus is the only known non-vertebrate animal to navigate and orient itself using the Milky Way. Dung beetles are not a single taxonomic group.
Coleoptera, beetles Scarabaeoidea, scarabs Geotrupidae, "earth-boring dung beetles" Scarabaeidae, "scarab beetles" Scarabaeinae, "true dung beetles" Aphodiinae, "small dung beetles" Systematic Position: Kingdom Animalia Phylum Arthropoda Subphylum Hexapoda Class Insecta Order Coleoptera Suborder Polyphaga Superfamily Scarabaeoidea Family Scarabaeidae ↑ Dung beetles live in many habitats, including desert and savannas, native and planted forests. They are influenced by the environmental context, do not prefer cold or dry weather, they are found on all continents except Antarctica. They eat the dung of herbivores and omnivores, prefer that produced by the latter. Many of them feed on mushrooms and decaying leaves and fruits. One type living in Central America, Deltochilum valgum, is a carnivore preying upon millipedes; those that eat dung do not need to eat or drink anything else, because the dung provides all the necessary nutrients. Most dung beetles search for dung using their sensitive sense of smell.
Some smaller species attach themselves to the dung-providers to wait for the dung. After capturing the dung, a dung beetle rolls it. Sometimes, dung beetles try to steal the dung ball from another beetle, so the dung beetles have to move away from a dung pile once they have rolled their ball to prevent it from being stolen. Dung beetles can roll up to 10 times their weight. Male Onthophagus taurus beetles can pull 1,141 times their own body weight: the equivalent of an average person pulling six double-decker buses full of people. A species of dung beetle navigates by polarization patterns in moonlight, the first animal known to do so. Dung beetles can navigate when only the Milky Way or clusters of bright stars are visible, making them the only insects known to orient themselves by the Milky Way; the eyes of dung beetles are superposition compound eyes typical of many scarabaeid beetles. The "rollers" bury a dung ball either for food storage or for making a brooding ball. In the latter case, two beetles, one male and one female, stay around the dung ball during the rolling process.
It is the male that rolls the ball, while the female hitch-hikes or follows behind. In some cases, the male and the female roll together; when a spot with soft soil is found, they stop and bury the ball mate underground. After the mating, one or both of them prepares the brooding ball; when the ball is finished, the female lays eggs inside it, a form of mass provisioning. Some species remain to safeguard their offspring; the dung beetle goes through a complete metamorphosis. The larvae live in brood balls made with dung prepared by their parents. During the larval stage, the beetle feeds on the dung surrounding it; the behavior of the beetles was poorly understood until the studies of Jean Henri Fabre in the late 19th century. For example, Fabre corrected the myth that a dung beetle would seek aid from other dung beetles when confronted by obstacles. By observation and experiment, he found the seeming helpers were in fact awaiting an opportunity to steal the roller's food source, they are used in ecological research as a good bioindicator group to examine the impacts from human activities on tropical biodiversity and ecosystem functioning, such as seed dispersal, soil bioturbation and nutrient cycling.
Dung beetles play a remarkable role in agriculture and tropical forests. By burying and consuming dung, they improve soil structure. Dung beetles have been further shown to improv
Bedouin
The Bedouin or Bedu are a grouping of nomadic Arab people who have inhabited the desert regions in North Africa, the Arabian Peninsula and the Levant. The English word bedouin comes from the Arabic badawī, which means "desert dweller", is traditionally contrasted with ḥāḍir, the term for sedentary people. Bedouin territory stretches from the vast deserts of North Africa to the rocky sands of the Middle East, they are traditionally divided into tribes, or clans, share a common culture of herding camels and goats. The vast majority of Bedouin adhere to Islam. Bedouins have been referred to by various names throughout history, including Qedarites in the Old Testament and Arabaa by the Assyrians, they are referred to as the ʾAʿrāb in the Quran. While many Bedouins have abandoned their nomadic and tribal traditions for a modern urban lifestyle, many retain traditional Bedouin culture such as retaining the traditional ʿašāʾir clan structure, traditional music, poetry and many other cultural practices and concepts.
Urbanised Bedouins organise cultural festivals held several times a year, in which they gather with other Bedouins to partake in and learn about various Bedouin traditions—from poetry recitation and traditional sword dances to playing traditional instruments and classes teaching traditional tent knitting. Traditions like camel riding and camping in the deserts are still popular leisure activities for urbanised Bedouins who live within close proximity to deserts or other wilderness areas; the English word bedouin comes from the Arabic badawī, which means "desert dweller", is traditionally contrasted with ḥāḍir, the term for sedentary people. The word bādiyah means visible land, in the sense of "plain" or "desert"; the term "Bedouin" therefore means "those in bādiyah" or "those in the desert". In English usage, the form "Bedouin" is used for the singular term, the plural being "Bedouins", as indicated by the Oxford English Dictionary, second edition; the term "Bedouin" uses the same root word as the Arabic noun for "the beginning".
Most Arabs believe the Bedouins to be the predecessors to settled Arabs, including the Nabataeans Arabs of the more westerly Levant region. According to a hadith, Caliph Umar ibn al-Khattab said of the Bedouin, "hey are the origin of the Arabs and the substance of Islam." and the word for the ethnicity itself may be influenced by that. A quoted Bedouin apothegm is "I am against my brother, my brother and I are against my cousin, my cousin and I are against the stranger" sometimes quoted as "I and my brother are against my cousin, I and my cousin are against the stranger." This saying signifies a hierarchy of loyalties based on the proximity of male kinship, beginning with the nuclear family through the lineage and the paternal tribe, and, in principle at least, to an entire genetic or linguistic group. Disputes are settled, interests are pursued, justice and order are dispensed and maintained by means of this framework, organized according to an ethic of self-help and collective responsibility.
The individual family unit consisted traditionally of three or four adults and any number of children. When resources were plentiful, several tents would travel together as a goum. While these groups were sometimes linked by patriarchal lineage, others were just as linked by marriage alliances. Sometimes, the association was based on acquaintance and familiarity, or no defined relation except for simple shared membership within a tribe; the next scale of interaction within groups was the ibn ʿamm or descent group of three to five generations. These were linked to goums, but where a goum would consist of people all with the same herd type, descent groups were split up over several economic activities, thus allowing a degree of'risk management'. Whilst the phrase "descent group" suggests purely a lineage-based arrangement, in reality these groups were fluid and adapted their genealogies to take in new members; the largest scale of tribal interactions is the tribe as a whole, led by a Sheikh, though the title refers to leaders in varying contexts.
The tribe claims descent from one common ancestor—as mentioned above. The tribal level is the level that mediated between the Bedouin and the outside governments and organizations. Distinct structure of the Bedouin society leads to long lasting rivalries between different clans. Bedouin traditionally had strong honor codes, traditional systems of justice dispensation in Bedouin society revolved around such codes; the bisha'a, or ordeal by fire, is a well-known Bedouin practice of lie detection. See also: Honor codes of the Bedouin, Bedouin systems of justice. Urbanized Bedouin are less to continue such traditions, instead opting for the codes of behavior that govern the wider settled community to which they belong. Livestock and herding, principally of goats and dromedary camels comprised the traditional livelihoods of Bedouins; these two animals were used for meat, dairy products, wool. Most of the staple foods that made up th
Gravity's Rainbow
Gravity's Rainbow is a 1973 novel by American writer Thomas Pynchon. Lengthy and featuring a large cast of characters, the narrative is set in Europe at the end of World War II, centers on the design and dispatch of V-2 rockets by the German military. In particular, it features the quest undertaken by several characters to uncover the secret of a mysterious device named the "Schwarzgerät", slated to be installed in a rocket with the serial number "00000". Traversing a wide range of knowledge, Gravity's Rainbow transgresses boundaries between high and low culture, between literary propriety and profanity, between science and speculative metaphysics, it shared the 1974 U. S. National Book Award for Fiction with A Crown of Feathers and Other Stories by Isaac Bashevis Singer. Although selected by the Pulitzer Prize jury on fiction for the 1974 Pulitzer Prize for Fiction, the Pulitzer Advisory Board was offended by its content, some of, described as "'unreadable,"turgid,"overwritten' and in parts'obscene'".
No Pulitzer Prize was awarded for fiction that year. The novel was nominated for the 1973 Nebula Award for Best Novel. Time named Gravity's Rainbow one of its "All-Time 100 Greatest Novels", a list of the best English-language novels from 1923 to 2005 and it is considered by many critics to be one of the greatest American novels written; the novel's title declares its ambition and sets into resonance the oscillation between doom and freedom expressed throughout the book. An example of the superfluity of meanings characteristic of Pynchon's work during his early years, Gravity's Rainbow refers to: The parabolic trajectory of a V-2 rocket: the "rainbow-shaped" path created by the missile as it moves under the influence of gravity, subsequent to the engine's deactivation The arc of the plot: Critics such as Weisenburger have found this trajectory to be cyclical or circular, like the true shape of a rainbow; this follows in the literary tradition of James Joyce's Finnegans Wake and Herman Melville's The Confidence-Man.
The statistical pattern of impacts from rocket-bombs, invoked in the novel by reference to the Poisson distribution The introduction of randomness into the science of physics through the development of quantum mechanics, breaking the assumption of a deterministic universe The animating effect of mortality on the human imaginationGravity's Rainbow is composed of four parts. The name "Beyond the Zero" refers to lack of total extinction of a conditioned stimulus; the events of this part occur during the Christmas Advent season of 1944 from December 18–26. The epigraph is a quotation from a pamphlet written by the rocket scientist Wernher von Braun and first published in 1962: "Nature does not know extinction. Everything science has taught me, continues to teach me, strengthens my belief in the continuity of our spiritual existence after death." The epigraph reflects themes of anticipated redemption and blurring of the sacred and secular, both of which pervade Part 1. "Part 2: Un Perm' au Casino Hermann Goering" contains eight episodes.
The events of this section span the five months from Christmas 1944 through to Whitsunday the following year. The misrepresentation or reinterpretation of identity is reflected in Slothrop's journey as well as the epigraph, attributed to Merian C. Cooper, speaking to Fay Wray prior to her starring role in King Kong, as recounted by Wray in the September 21, 1969, issue of The New York Times: "You will have the tallest, darkest leading man in Hollywood." "Part 3: In the Zone" comprises 32 episodes. The action of Part 3 is set during the summer of 1945 with analepses to the time period of Part 2 with most events taking place between May 18 and August 6; the epigraph is taken from The Wizard of Oz, spoken by Dorothy as she arrives in Oz and shows her disorientation with the new environment: "Toto, I have a feeling we're not in Kansas any more...". "Part 4: The Counterforce" is made up of 12 episodes. The plot of this part begins shortly after August 6, 1945 and covers the period up to September 14 of that same year.
The simple epigraphical quotation, "What?" is attributed to Richard M. Nixon, was added after the galleys of the novel had been printed to insinuate the President's involvement in the unfolding Watergate scandal; the original quotation for this section was an excerpt from the lyrics to the Joni Mitchell song "Cactus Tree", so the change in quotation jumped a large cultural divide. The opening pages of the novel follow Pirate Prentice, an employee of the Special Operations Executive, first in his dreams, around his house in wartime London. Pirate's associate Teddy Bloat photographs a map depicting the sexual encounters of U. S. Army Lt. Tyrone Slothrop, an employee of a fictional technical intelligence unit called ACHTUNG; each of Slothrop's sexual encounters in London appears to precede a V-2 rocket strike in the same place by several days. Employees of a fictional top secret psychological warfare agency called PISCES, headquartered at a former insane asylum known as "The White Visitation" investigate Slothrop's apparent precognition, including statistician Roger Mexico and Pavlovian behavioral psychologist Edward W. Pointsman, among others.
Slothrop's
Symbiosis
Symbiosis is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasitic. The organisms, each termed a symbiont, may be of different species. In 1879, Heinrich Anton de Bary defined it as "the living together of unlike organisms"; the term was subject to a century-long debate about whether it should denote mutualism, as in lichens. Symbiosis can be obligatory, which means that one or both of the symbionts depend on each other for survival, or facultative when they can live independently. Symbiosis is classified by physical attachment; when one organism lives on the surface of another, such as head lice on humans, it is called ectosymbiosis. The definition of symbiosis was a matter of debate for 130 years. In 1877, Albert Bernhard Frank used the term symbiosis to describe the mutualistic relationship in lichens. In 1879, the German mycologist Heinrich Anton de Bary defined it as "the living together of unlike organisms".
The definition has varied among scientists, with some advocating that it should only refer to persistent mutualisms, while others thought it should apply to all persistent biological interactions, in other words mutualisms, commensalism, or parasitism, but excluding brief interactions such as predation. Current biology and ecology textbooks use the latter "de Bary" definition, or an broader one where symbiosis means all interspecific interactions. In 1949, Edward Haskell proposed an integrative approach, proposing a classification of "co-actions" adopted by biologists as "interactions". Biological interactions can involve individuals of the same species or individuals of different species; these can be further classified by either the mechanism of the interaction or the strength and direction of their effects. Relationships can be obligate, meaning that one or both of the symbionts depend on each other for survival. For example, in lichens, which consist of fungal and photosynthetic symbionts, the fungal partners cannot live on their own.
The algal or cyanobacterial symbionts in lichens, such as Trentepohlia, can live independently, their symbiosis is, facultative. Endosymbiosis is any symbiotic relationship in which one symbiont lives within the tissues of the other, either within the cells or extracellularly. Examples include diverse microbiomes, nitrogen-fixing bacteria that live in root nodules on legume roots. Ectosymbiosis is any symbiotic relationship in which the symbiont lives on the body surface of the host, including the inner surface of the digestive tract or the ducts of exocrine glands. Examples of this include ectoparasites such as lice. Competition can be defined as an interaction between organisms or species, in which the fitness of one is lowered by the presence of another. Limited supply of at least one resource used by both facilitates this type of interaction, although the competition may exist over other'amenities', such as females for reproduction. Mutualism or interspecies reciprocal altruism is a long-term relationship between individuals of different species where both individuals benefit.
Mutualistic relationships may be either obligate for both species, obligate for one but facultative for the other, or facultative for both. A large percentage of herbivores have mutualistic gut flora to help them digest plant matter, more difficult to digest than animal prey; this gut flora is made up of cellulose-digesting protozoans or bacteria living in the herbivores' intestines. Coral reefs are the result of mutualisms between coral organisms and various types of algae which live inside them. Most land plants and land ecosystems rely on mutualisms between the plants, which fix carbon from the air, mycorrhyzal fungi, which help in extracting water and minerals from the ground. An example of mutualism is the relationship between the ocellaris clownfish that dwell among the tentacles of Ritteri sea anemones; the territorial fish protects the anemone from anemone-eating fish, in turn the stinging tentacles of the anemone protect the clownfish from its predators. A special mucus on the clownfish protects it from the stinging tentacles.
A further example is a fish which sometimes lives together with a shrimp. The shrimp cleans up a burrow in the sand in which both the shrimp and the goby fish live; the shrimp is blind, leaving it vulnerable to predators when outside its burrow. In case of danger, the goby touches the shrimp with its tail to warn it; when that happens both the shrimp and goby retreat into the burrow. Different species of gobies clean up ectoparasites in other fish another kind of mutualism. A non-obligate symbiosis is seen in encru
Rabbit
Rabbits are small mammals in the family Leporidae of the order Lagomorpha. Oryctolagus cuniculus includes the European rabbit species and its descendants, the world's 305 breeds of domestic rabbit. Sylvilagus includes 13 wild rabbit species, among them the 7 types of cottontail; the European rabbit, introduced on every continent except Antarctica, is familiar throughout the world as a wild prey animal and as a domesticated form of livestock and pet. With its widespread effect on ecologies and cultures, the rabbit is, in many areas of the world, a part of daily life—as food, clothing, a companion, as a source of artistic inspiration. Male rabbits are called bucks. An older term for an adult rabbit is coney. Another term for a young rabbit is bunny, though this term is applied informally to rabbits especially domestic ones. More the term kit or kitten has been used to refer to a young rabbit. A group of rabbits is known as a nest. A group of baby rabbits produced from a single mating is referred to as a litter, a group of domestic rabbits living together is sometimes called a herd.
Rabbits and hares were classified in the order Rodentia until 1912, when they were moved into a new order, Lagomorpha. Below are some of the species of the rabbit. Order Lagomorpha Family Leporidae Hares are precocial, born mature and mobile with hair and good vision, while rabbits are altricial, born hairless and blind, requiring closer care. Hares live a solitary life in a simple nest above the ground, while most rabbits live in social groups underground in burrows or warrens. Hares are larger than rabbits, with ears that are more elongated, with hind legs that are larger and longer. Hares have not been domesticated, while descendants of the European rabbit are bred as livestock and kept as pets. Rabbits have long been domesticated. Beginning in the Middle Ages, the European rabbit has been kept as livestock, starting in ancient Rome. Selective breeding has generated a wide variety of rabbit breeds, many of which are kept as pets; some strains of rabbit have been bred as research subjects. As livestock, rabbits are bred for their fur.
The earliest breeds were important sources of meat, so became larger than wild rabbits, but domestic rabbits in modern times range in size from dwarf to giant. Rabbit fur, prized for its softness, can be found in a broad range of coat colors and patterns, as well as lengths; the Angora rabbit breed, for example, was developed for its long, silky fur, hand-spun into yarn. Other domestic rabbit breeds have been developed for the commercial fur trade, including the Rex, which has a short plush coat; because the rabbit's epiglottis is engaged over the soft palate except when swallowing, the rabbit is an obligate nasal breather. Rabbits have two sets of one behind the other; this way they can be distinguished from rodents, with which they are confused. Carl Linnaeus grouped rabbits and rodents under the class Glires. However, recent DNA analysis and the discovery of a common ancestor has supported the view that they do share a common lineage, thus rabbits and rodents are now referred to together as members of the superorder Glires.
Since speed and agility are a rabbit's main defenses against predators, rabbits have large hind leg bones and well developed musculature. Though plantigrade at rest, rabbits are on their toes while running, assuming a more digitigrade form. Rabbits use their strong claws for defense; each front foot has four toes plus a dewclaw. Each hind foot has four toes. Most wild rabbits have full, egg-shaped bodies; the soft coat of the wild rabbit is agouti in coloration. The tail of the rabbit is dark on white below. Cottontails have white on the top of their tails; as a result of the position of the eyes in its skull, the rabbit has a field of vision that encompasses nearly 360 degrees, with just a small blind spot at the bridge of the nose. The anatomy of rabbits' hind limbs are structurally similar to that of other land mammals and contribute to their specialized form of locomotion; the Bones of the hind limbs consist of long bones as well as short bones. These bones are created through endochondral ossification during development.
Like most land mammals, the round head of the femur articulates with the acetabulum of the ox coxae. The femur articulates with the tibia, but not the fibula, fused to the tibia; the tibia and fibula articulate with the tarsals of the pes called the foot. The hind limbs of the rabbit are longer than the front limbs; this allows them to produce their hopping form of locomotion. Longer hind limbs are more capable of producing faster speeds. Hares, which have longer legs than cottontail rabbits, are able to move faster. Rabbits stay just on their toes; the hind feet have four long toes that allow for this and are webbed to prevent them from spreading when hopping. Rabbits do not have paw
Cattle
Cattle—colloquially cows—are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, are most classified collectively as Bos taurus. Cattle are raised as livestock for meat, for milk, for hides, which are used to make leather, they are used as riding animals and draft animals. Another product of cattle is dung, which can be used to create fuel. In some regions, such as parts of India, cattle have significant religious meaning. Cattle small breeds such as the Miniature Zebu, are kept as pets. Around 10,500 years ago, cattle were domesticated from as few as 80 progenitors in central Anatolia, the Levant and Western Iran. According to an estimate from 2011, there are 1.4 billion cattle in the world. In 2009, cattle became one of the first livestock animals to have a mapped genome; some consider cattle the oldest form of wealth, cattle raiding one of the earliest forms of theft. Cattle were identified as three separate species: Bos taurus, the European or "taurine" cattle.
The aurochs is ancestral to both taurine cattle. These have been reclassified as one species, Bos taurus, with three subspecies: Bos taurus primigenius, Bos taurus indicus, Bos taurus taurus. Complicating the matter is the ability of cattle to interbreed with other related species. Hybrid individuals and breeds exist, not only between taurine cattle and zebu, but between one or both of these and some other members of the genus Bos – yaks and gaur. Hybrids such as the beefalo breed can occur between taurine cattle and either species of bison, leading some authors to consider them part of the genus Bos, as well; the hybrid origin of some types may not be obvious – for example, genetic testing of the Dwarf Lulu breed, the only taurine-type cattle in Nepal, found them to be a mix of taurine cattle and yak. However, cattle cannot be hybridized with more distantly related bovines such as water buffalo or African buffalo; the aurochs ranged throughout Europe, North Africa, much of Asia. In historical times, its range became restricted to Europe, the last known individual died in Mazovia, Poland, in about 1627.
Breeders have attempted to recreate cattle of similar appearance to aurochs by crossing traditional types of domesticated cattle, creating the Heck cattle breed. The noun cattle encompasses both sexes; the singular, technically means the female, the male being bull. The plural form cows is sometimes used colloquially to refer to both sexes collectively, as e.g. in a herd, but that usage can be misleading as the speaker's intent may indeed be just the females. The bovine species per se is dimorphic. Cattle did not originate as the term for bovine animals, it was borrowed from Anglo-Norman catel, itself from medieval Latin capitale'principal sum of money, capital', itself derived in turn from Latin caput'head'. Cattle meant movable personal property livestock of any kind, as opposed to real property; the word is a variant of chattel and related to capital in the economic sense. The term replaced earlier Old English feoh ` property', which survives today as fee; the word "cow" came via Anglo-Saxon cū, from Common Indo-European gʷōus = "a bovine animal", compare Persian: gâv, Sanskrit: go-, Welsh: buwch.
The plural cȳ became ki or kie in Middle English, an additional plural ending was added, giving kine, but kies and others. This is the origin of the now archaic English plural, "kine"; the Scots language singular is coo or cou, the plural is "kye". In older English sources such as the King James Version of the Bible, "cattle" refers to livestock, as opposed to "deer" which refers to wildlife. "Wild cattle" may refer to undomesticated species of the genus Bos. Today, when used without any other qualifier, the modern meaning of "cattle" is restricted to domesticated bovines. In general, the same words are used in different parts of the world, but with minor differences in the definitions; the terminology described here contrasts the differences in definition between the United Kingdom and other British-influenced parts of the world such as Canada, New Zealand and the United States. An "intact" adult male is called a bull. A wild, unmarked bull is known as a micky in Australia. An unbranded bovine of either sex is called a maverick in the Canada.
An adult female that has had a calf is a cow. A young female before she has had a calf of her own and is under three years of age is called a heifer. A young female that has had only one calf is called a first-calf heifer. Young cattle of both sexes are called calves until they are weaned weaners until they are a year old in some areas. After that, they are referred to as stirks if between one and two years of age. A castrated male is called a steer in the United States.
Camel
A camel is an even-toed ungulate in the genus Camelus that bears distinctive fatty deposits known as "humps" on its back. Camels have long been domesticated and, as livestock, they provide food and textiles; as working animals, camels—which are uniquely suited to their desert habitats—are a vital means of transport for passengers and cargo. There are three surviving species of camel; the one-humped dromedary makes up 94% of the world's camel population, the two-humped Bactrian camel makes up the remainder. The Wild Bactrian camel is now critically endangered; the word camel is derived via Latin: camelus and Greek: κάμηλος from Hebrew or Phoenician: gāmāl. Used informally, "camel" refers to any of the seven members of the family Camelidae: the dromedary, the Bactrian, the wild Bactrian, plus the llama, the alpaca, the guanaco, the vicuña; the dromedary known as the Arabian camel, inhabits the Middle East and the Horn of Africa, while the Bactrian inhabits Central Asia, including the historical region of Bactria.
The critically endangered wild Bactrian is found only in remote areas of northwest China and Mongolia. An extinct species of camel in the separate genus Camelops, known as C. hesternus, lived in western North America until humans entered the continent at the end of the Pleistocene. The average life expectancy of a camel is 40 to 50 years. A full-grown adult camel stands 1.85 m at 2.15 m at the hump. Camels can sustain speeds of up to 40 km/h. Bactrian camels dromedaries 300 to 600 kg; the widening toes on a camel's hoof provide supplemental grip for varying soil sediments. The male dromedary camel has an organ called a dulla in its throat, a large, inflatable sac he extrudes from his mouth when in rut to assert dominance and attract females, it resembles a long, pink tongue hanging out of the side of its mouth. Camels mate by having both male and female sitting on the ground, with the male mounting from behind; the male ejaculates three or four times within a single mating session. Camelids are the only ungulates to mate in a sitting position.
Camels do not directly store water in their humps. Concentrating body fat in their humps minimizes the insulating effect fat would have if distributed over the rest of their bodies, helping camels survive in hot climates; when this tissue is metabolized, it yields more than one gram of water for every gram of fat processed. This fat metabolization, while releasing energy, causes water to evaporate from the lungs during respiration: overall, there is a net decrease in water. Camels have a series of physiological adaptations that allow them to withstand long periods of time without any external source of water; the dromedary camel can drink as as once every 10 days under hot conditions, can lose up to 30% of its body mass due to dehydration. Unlike other mammals, camels' red blood cells are oval rather than circular in shape; this facilitates the flow of red blood cells during dehydration and makes them better at withstanding high osmotic variation without rupturing when drinking large amounts of water: a 600 kg camel can drink 200 L of water in three minutes.
Camels are able to withstand changes in body temperature and water consumption that would kill most other animals. Their temperature ranges from 34 °C at dawn and increases to 40 °C by sunset, before they cool off at night again. In general, to compare between camels and the other livestock, camels lose only 1.3 liters of fluid intake every day while the other livestock lose 20 to 40 liters per day. Maintaining the brain temperature within certain limits is critical for animals. Camels sweat when ambient temperatures reach 49 °C. Any sweat that does occur evaporates at the skin level rather than at the surface of their coat. Camels can withstand losing 25% of their body weight to sweating, whereas most other mammals can withstand only about 12–14% dehydration before cardiac failure results from circulatory disturbance; when the camel exhales, water vapor becomes trapped in their nostrils and is reabsorbed into the body as a means to conserve water. Camels eating green herbage can ingest sufficient moisture in milder conditions to maintain their bodies' hydrated state without the need for drinking.
The camels' thick coats insulate them from the intense heat radiated from desert sand. During the summer the coat becomes lighter in color, reflecting light as well as helping avoid sunburn; the camel's long legs help by keeping its body farther from the ground, which can heat up to 70 °C. Dromedaries have a pad of thick tissue over the sternum called the pedestal; when the animal lies down in a sternal recumbent position, the pedestal raises the body from the hot surface and allows cooling air to pass under the body. Camels' mouths have a thick leathery lining. Long eyelashes and ear hairs, together with nostrils, form a barrier against sand. If sand gets lodged in their eyes, they can dislodge it using their transparent t
