Editing Camel (section)

===Ecological and behavioral adaptations===
{{anchor |Hump}}

[[File:Teve 3.jpg |thumb |Camel humps store fat for when food is scarce. If a camel uses the fat, the hump becomes limp and droops.]]

It is a common myth that a camel stores water in its hump,<ref>{{cite web|url=https://www.loc.gov/everyday-mysteries/zoology/item/how-much-water-does-a-camels-hump-hold/#:~:text=A%20camel's%20hump%20does%20not,become%20limp%20and%20droop%20down.|publisher=Library of Congress|accessdate=2025-05-06|title=How much water does a camel’s hump hold?}}</ref> but the humps in fact are reservoirs of fatty tissue, which can be used as a reserve source of calories, not water.  When this tissue is metabolized, it yields a greater mass of water than that of the fat processed. This [[lipolysis |fat metabolization]], while releasing energy, causes water to evaporate from the lungs during [[breathing |respiration]] (as oxygen is required for the metabolic process): overall, there is a net decrease in water.<ref name=vannjones>{{cite web |url=http://www.djur.cob.lu.se/Djurartiklar/Kamel.html |title=What secrets lie within the camel's hump? |first=Kerstin |last=Vann Jones |publisher=[[Lund University]] |location=[[Sweden]] |access-date=7 January 2008 |url-status=live |archive-url=https://web.archive.org/web/20090523104134/http://www.djur.cob.lu.se/Djurartiklar/Kamel.html |archive-date=23 May 2009}}</ref><ref name=rastogi71>{{cite book |publisher=[[New Age International]] |isbn=9788122412796 |last=Rastogi |first=S. C. |title=Essentials Of Animal Physiology |year=1971 |pages=180–181}}</ref>

[[File:Camel portrait.jpg |upright |thumb |alt=A portrait of a camel with a visibly thick mane |A camel's thick coat is one of its many adaptations that aid it in desert-like conditions.<!---Don't move this image up or it causes a break in the text on wide screens--->]]
[[File:Eylcamel.jpg |thumb |alt=A leashed pack camel |A camel in [[wildlife of Somalia |Somalia]], which has the world's largest camel population<ref name="Bernstein"/>]]
Camels have a series of physiological adaptations that allow them to withstand long periods of time without any external source of water.<ref name="roberts86">{{cite book |last=Roberts |first=Michael Bliss Vaughan |title=Biology: A Functional Approach |publisher=[[Nelson Thornes]] |year=1986 |isbn=9780174480198 |pages=234–235, 241}}</ref> The dromedary camel can drink as seldom as once every 10 days even under very hot conditions, and can lose up to 30% of its body mass due to dehydration.<ref>{{Cite web |url=http://unesdoc.unesco.org/images/0022/002240/224033e.pdf |archive-url=https://web.archive.org/web/20151109175143/http://unesdoc.unesco.org/images/0022/002240/224033e.pdf |archive-date=2015-11-09 |url-status=live |title=The Camel from Tradition To Modern Times |author=[[UNESCO]] }}</ref> They can drink up to 20 gallons at a time but this is stored in the animal's bloodstream, not, as popularly believed, in its humps.<ref>{{cite web|url=https://www.loc.gov/everyday-mysteries/zoology/item/how-much-water-does-a-camels-hump-hold/#:~:text=A%20camel's%20hump%20does%20not,become%20limp%20and%20droop%20down.|publisher=Library of Congress|accessdate=2025-05-06|title=How much water does a camel’s hump hold?}}</ref>

Unlike other mammals, camels' [[red blood cell]]s are oval rather than circular in shape. This facilitates the flow of red blood cells during dehydration<ref>{{cite journal |last1=Eitan |first1=A |last2=Aloni |first2=B |last3=Livne |first3=A |title=Unique properties of the camel erythrocyte membraneII. Organization of membrane proteins |journal=[[Biochimica et Biophysica Acta (BBA) - Biomembranes]] |volume=426 |issue=4 |pages=647–58 |year=1976 |doi=10.1016/0005-2736(76)90129-2 |pmid=816376 }}</ref> and makes them better at withstanding high [[osmosis |osmotic]] variation without rupturing when drinking large amounts of water.<ref>{{cite web |url=http://www.zoo-hannover.de/zoo-hannover/en/zoo_v3/tiere_attraktionen/tiere_az/tiere_detail_726.html |archive-url=https://web.archive.org/web/20051025001139/http://www.zoo-hannover.de/zoo-hannover/en/zoo_v3/tiere_attraktionen/tiere_az/tiere_detail_726.html |archive-date=25 October 2005 |title= Dromedary |publisher=Hannover Zoo |access-date=8 January 2008}}</ref><ref name=mares99>{{cite book |publisher=University of Oklahoma Press |isbn=9780806131467 |editor1-last=Mares |editor2-last=Michael A. |title=Deserts |year=1999 |chapter=Camel |pages=96–97 |first=E. Anette |last=Halpern |chapter-url=https://books.google.com/books?id=g3CbqZtaF4oC&pg=PA96 |url-status=live |archive-url=https://web.archive.org/web/20160429083434/https://books.google.com/books?id=g3CbqZtaF4oC&lpg=PP1&pg=PA96 |archive-date=2016-04-29}}</ref>

Camels are able to withstand changes in [[body temperature]] and water consumption that would kill most other mammals. Their temperature ranges from {{convert |34 |°C |°F |0 |abbr=on}} at dawn and steadily increases to {{convert |40 |°C |°F |0 |abbr=on}} by sunset, before they cool off at night again.<ref name=roberts86 /> 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.<ref>Breulmann, M., Böer, B., Wernery, U., Wernery, R., El Shaer, H., Alhadrami, G., ... Norton, J. (2007). "The Camel From Tradition to Modern Times" (PDF). [[UNESCO]] DOHA OFFICE.</ref> Maintaining the brain temperature within certain limits is critical for animals; to assist this, camels have a [[rete mirabile]], a complex of arteries and veins lying very close to each other which utilizes countercurrent blood flow to cool blood flowing to the brain.<ref name="Inside Nature's Giants">[[Inside Nature's Giants]]. [[Channel 4 (UK)]] documentary. Transmitted 30 August 2011</ref> Camels rarely sweat, even when ambient temperatures reach {{convert |49 |°C |°F |0 |abbr=on}}.<ref name="nationalgeo-dromedary">{{cite web |title=Arabian (Dromedary) Camel |access-date=25 November 2012 |publisher=[[National Geographic Society]] |work=National Geographic |date=10 May 2011 |url=http://animals.nationalgeographic.com/animals/mammals/dromedary-camel/ |url-status=dead |archive-url=https://web.archive.org/web/20121119062839/http://animals.nationalgeographic.com/animals/mammals/dromedary-camel |archive-date=19 November 2012}}</ref> Any sweat that does occur evaporates at the skin level rather than at the surface of their coat; the [[heat of vaporization]] therefore comes from body heat rather than ambient heat. Camels can withstand losing 25% of their body weight in water, whereas most other mammals can withstand only about 12–14% dehydration before [[Congestive heart failure |cardiac failure]] results from circulatory disturbance.<ref name=mares99/>

When the camel exhales, [[water vapor]] becomes trapped in their [[nostrils]] and is reabsorbed into the body as a means to conserve water.<ref>{{cite news |url=https://www.nytimes.com/1981/07/12/travel/a-pilgrimage-to-a-mystic-s-hermitage-in-algeria.html |title=A Pilgrimage To A Mystic's Hermitage In Algeria |newspaper= [[The New York Times]] |date=12 July 1981 |access-date=7 March 2009 |first=Paul |last=Lewis |url-status=live |archive-url=https://web.archive.org/web/20090804093505/http://www.nytimes.com/1981/07/12/travel/a-pilgrimage-to-a-mystic-s-hermitage-in-algeria.html |archive-date=4 August 2009 }}</ref> Camels eating green herbage can ingest sufficient moisture in milder conditions to maintain their bodies' hydrated state without the need for drinking.<ref name=fao94>{{cite book |chapter-url=http://www.fao.org/docrep/t0690e/t0690e09.htm |title=A manual for primary animal health care worker |chapter=Camels, llamas and alpacas |year=1994 |series=[[FAO Animal Health Manual]] |publisher=[[FAO Agriculture and Consumer Protection]] |url-status=live |archive-url=https://web.archive.org/web/20080727212250/http://www.fao.org/docrep/t0690e/t0690e09.htm |archive-date=2008-07-27}}</ref>

[[File:Camels in Dubai 2.jpg |right |thumb |Domesticated camel calves lying in sternal recumbency, which aids heat loss]]
The camel's thick coat insulates it from the intense heat radiated from desert sand; a shorn camel must sweat 50% more to avoid overheating.<ref>{{cite book |last=Schmidt-Nielsen |first=K. |year=1964 |title=Desert Animals: Physiological Problems of Heat and Water |location=New York |publisher=[[Oxford University Press]] (OUP)}} Cited in {{cite web |url=http://www.bio.davidson.edu/Courses/anphys/1999/Blackwell/Fur.htm |title=Coat of fur on the camel |archive-url=https://web.archive.org/web/20030225103329/http://www.bio.davidson.edu/Courses/anphys/1999/Blackwell/Fur.htm |archive-date=February 25, 2003 |website=[[Davidson College]]}}</ref> During the summer the coat becomes lighter in color, reflecting light as well as helping avoid sunburn.<ref name=mares99 /> The camel's long legs help by keeping its body farther from the ground, which can heat up to {{convert |70 |°C |°F |0 |abbr=on}}.<ref name=bronxzoo>{{cite web |author=Bronx Zoo |title=Camel Adaptations |access-date=29 November 2012 |url=http://www.bronxzoo.com/files/engage.html |publisher=[[Wildlife Conservation Society]] |format=Flash |archive-url=https://web.archive.org/web/20120626071454/http://www.bronxzoo.com/files/engage.html |archive-date=26 June 2012}}</ref><ref name=rundel05>{{cite book |publisher=[[Cambridge University Press]] (CUP) |isbn=9780521021418 |last1=Rundel |first1=Philip Wilson |first2=Arthur C. |last2=Gibson |title=Ecological Communities And Processes in a Mojave Desert Ecosystem: Rock Valley, Nevada |date=30 September 2005 |chapter=Adaptations of Mojave Desert Animals |page=130 }}</ref> 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.<ref name="Inside Nature's Giants"/>

Camels' mouths have a thick leathery lining, allowing them to chew thorny desert plants. Long eyelashes and ear hairs, together with nostrils that can close, form a barrier against sand. If sand gets lodged in their eyes, they can dislodge it using their translucent [[third eyelid]] (also known as the nictitating membrane). The camels' gait and widened feet help them move without sinking into the sand.<ref name=bronxzoo /><ref name=silverstein08>{{cite book |publisher=Twenty-First Century Books |isbn=9780822534341 |last1=Silverstein |first1=Alvin |first2=Virginia B |last2=Silverstein |first3=Virginia |last3=Silverstein<!--No, really.--> |first4=Laura |last4=Silverstein Nunn |title=Adaptation |year=2008 |pages=[https://archive.org/details/adaptation0000silv/page/42 42–43] |url=https://archive.org/details/adaptation0000silv/page/42 }}</ref>

The [[kidney]]s and [[intestines]] of a camel are very efficient at reabsorbing water. Camels' kidneys have a 1:4 [[Renal cortex |cortex]] to [[Renal medulla |medulla ratio]].<ref>{{Cite web |url=https://www.researchgate.net/publication/249746665 |title=Morphometric analysis of heart, kidneys and adrenal glands in dromedary camel calves (PDF Download Available) |website=ResearchGate |language=en |access-date=2017-03-03 |url-status=live |archive-url=https://web.archive.org/web/20170304040835/https://www.researchgate.net/publication/249746665_Morphometric_analysis_of_heart_kidneys_and_adrenal_glands_in_dromedary_camel_calves |archive-date=2017-03-04}}</ref> Thus, the medullary part of a camel's kidney occupies twice as much area as a cow's kidney. Secondly, [[renal corpuscles]] have a smaller diameter, which reduces surface area for filtration. These two major anatomical characteristics enable camels to conserve water and limit the volume of urine in extreme desert conditions.<ref name="Rehan08">Rehan S and AS Qureshi, 2006. Microscopic evaluation of the heart, kidneys and adrenal glands of one-humped camel calves (Camelus dromedarius) using semi automated image analysis system. J Camel Pract Res. 13(2): 123
</ref> [[Camel urine]] comes out as a thick syrup, and camel faeces are so dry that they do not require drying when used to fuel fires.<ref name=davidson06 /><ref name="davidson-kidney">{{cite web |url=http://www.bio.davidson.edu/Courses/anphys/1999/Blackwell/Kidney.htm |publisher=Davidson College |title=Kidneys and Concentrated Urine |work= Temperature and Water Relations in Dromedary Camels (Camelus dromedarius) |archive-url=https://web.archive.org/web/20030225104431/http://www.bio.davidson.edu/Courses/anphys/1999/Blackwell/Kidney.htm |archive-date=February 25, 2003}}</ref><ref name=junglestore>{{cite web |title=Fun facts about the Camel |work=The Jungle Store |access-date=3 December 2012 |url=http://www.thejunglestore.com/Camels |archive-url=https://web.archive.org/web/20121117070148/http://www.thejunglestore.com/Camels |archive-date=17 November 2012 }}</ref><ref name=fedewa00 />

The camel [[immune system]] differs from those of other mammals. Normally, the Y-shaped [[antibody]] molecules consist of two heavy (or long) chains along the length of the Y, and two light (or short) chains at each tip of the Y.<ref name="Camelized" /> Camels, in addition to these, also have antibodies made of only two heavy chains, a trait that makes them smaller and more durable.<ref name="Camelized" /> These "heavy-chain-only" antibodies, discovered in 1993, are thought to have developed 50&nbsp;million years ago, after camelids split from ruminants and pigs.<ref name="Camelized" >{{cite journal |last1=Koenig |first1=R. |department=Veterinary Medicine |title='Camelized' Antibodies Make Waves |journal=[[Science (journal) |Science]] |volume=318 |issue=5855 |page=1373 |year=2007 |pmid=18048665 |doi=10.1126/science.318.5855.1373 |s2cid=71028674}}</ref>

The parasite ''[[Trypanosoma evansi]]'' causes the disease [[surra]] in camels.<ref name="Sazmand-Joachim-2017">{{cite journal |last1=Sazmand |first1=Alireza |last2=Joachim |first2=Anja |title=Parasitic diseases of camels in Iran (1931–2017) – a literature review |journal=[[Parasite (journal) |Parasite]] |publisher=[[EDP Sciences]] |volume=24 |year=2017 |issn=1776-1042 |doi=10.1051/parasite/2017024 |pages=1–15 |s2cid=13783061 |pmid=28617666 |pmc=5479402 |id=Article Number 21}}</ref>{{RP |page=2}}