Utente:Panjabi/Prove: differenze tra le versioni

Versione delle 17:10, 30 nov 2012

Versione attuale delle 16:13, 12 ott 2021

(7 versioni intermedie di 6 utenti non mostrate)

Riga 49:

}}

La '''giraffa''' ('''''Giraffa camelopardalis''''' <span style="font-variant: small-caps">{{zoo|[[Carl von Linné|Linnaeus]], [[|1758]]</span>}}) è un [[mammifero]] [[Artiodactyla|artiodattilo]] [[africa]]no; è il più alto animale terrestre vivente, nonché il [[ruminante]] di maggiori dimensioni. Il suo [[Nomenclatura binomiale|nome scientifico]] si riferisce al suo aspetto simile a un [[Camelus|cammello]] e alle macchie colorate che ne ornano il manto. È facilmente riconoscibile per il collo e le zampe estremamente lunghi, per i suoi [[ossiconi]] simili a corna e la caratteristica colorazione. Misura 5-6 m di altezza, mentre il peso varia dai circa 1600 kg per i maschi ai circa 830 kg per le femmine. Appartiene alla [[Famiglia (tassonomia)|famiglia]] dei [[Giraffidae|Giraffidi]], così come il suo unico parente attuale, l'[[Okapia johnstoni|okapi]]. Se ne riconoscono nove sottospecie, che differiscono tra loro per la colorazione del mantello.

L'areale della giraffa, piuttosto frammentato, si estende dal [[Ciad]], a nord, fino al [[Sudafrica]], a sud, e dal [[Niger]], a ovest, fino alla [[Somalia]], a est. Le giraffe vivono generalmente nelle [[Savana|savane]], nelle [[Prateria|praterie]] e nelle [[Bosco|boscaglie]] aperte. Si nutrono soprattutto di foglie di [[acacia]], che brucano ad altezze non raggiungibili dalla maggior parte degli altri erbivori. Loro unici nemici naturali sono i [[Panthera leo|leoni]], ma i piccoli possono cadere vittima anche di leopardi, [[Crocuta crocuta|iene macchiate]] e [[Lycaon pictus|licaoni]]. Gli esemplari adulti non stringono stretti rapporti sociali con i conspecifici, ma possono raggrupparsi in aggregazioni libere con altri esemplari che si spostano nella stessa direzione. I maschi stabiliscono gerarchie sociali attraverso il cosiddetto ''necking'', cioè combattimenti nei quali il collo viene impiegato come arma. Solo ai maschi dominanti è consentito accoppiarsi con le femmine, che sono le uniche a prendersi cura dell'allevamento dei piccoli.

Riga 56:

==Etimologia==

Il nome «giraffa» trae origine dalla parola [[Lingua araba|araba]] ''zarafa'' (زرافة), forse derivata a sua volta da un termine africano<ref name=OED/>. Tale parola è stata tradotta come «[colei che] cammina veloce»<ref name=kingdon/>. Nel [[Medioevo]] la specie era nota anche come ''jarraf'', ''ziraph'' e ''gerfauntz''<ref name=OED/>. È possibile che il termine derivi dal nome con il quale l'animale è noto in [[lingua somala]], ''Geri''<ref>{{citeCita booklibro|authorautore=Peust, C.|contributioncontributo=Some Cushitic Etymologies|editorscuratore=Dolgopolʹskiĭ, A.; Takács, G.; Jungraithmayr, H|yearanno=2009|titletitolo=Semito-Hamitic Festschrift for A.B. Dolgopolsky and H. Jungraithmayr|publishereditore=Reimer|pagespp=257–60|isbn=3-496-02810-6}}</ref>. Il nome [[Lingua italiana|italiano]] ''giraffa'' risale agli anni '90 del XVI secolo<ref name=OED>{{citeCita web|url=http://etymonline.com/?term=giraffe|titletitolo=Giraffe|publishereditore=Online Etymology Dictionary|accessdateaccesso=1º novembre 2011-11-01}}</ref>. La forma inglese ''Giraffe'', invece, derivata dal [[Lingua francese|francese]] ''girafe'', risale al 1600 circa<ref name=OED/>. Il nome specifico ''camelopardalis'' è il termine con il quale l'animale era noto in [[latino]]<ref>{{CiteCita web|url=http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0059%3Aentry%3Dcamelopardalis|titletitolo= camelopardalis|publishereditore=A Latin Dictionary, Perseus Digital Library|accessdateaccesso=2011-11-23 novembre 2011}}</ref>.

''Kameelperd'' è anche il nome con cui la specie è nota in [[lingua afrikaans]]<ref name=walker>{{citeCita booklibro|authorautore=Walker, C.|yearanno=1997|titletitolo=Signs of the Wild|publishereditore=Struik|pagep=142|isbn=1-86825-896-3}}</ref>. Tra gli altri nomi africani con cui viene indicato l'animale ricordiamo ''Ekorii'' (ateso), ''Kanyiet'' (elgon), ''Nduida'' (gikuyu), ''Tiga'' (kalenjin e luo), ''Ndwiya'' (kamba), ''Nudululu'' (kihehe), ''Ntegha'' (kinyaturu), ''Ondere'' (lugbara), ''Etiika'' (luhya), ''Kuri'' (ma'di), ''Oloodo-kirragata'' od ''Olchangito-oodo'' (maasai), ''Lenywa'' (meru), ''Hori'' (pare), ''Lment'' (samburu) e ''Twiga'' ([[Lingua swahili|swahili]] e altre lingue minori) nell'Africa orientale<ref name=Kingdon1988/>; e ''Tutwa'' ([[Lingua lozi|lozi]]), ''Nthutlwa'' ([[Lingua tsonga|shangaan]]), ''Indlulamitsi'' ([[Lingua swati|siswati]]), ''Thutlwa'' ([[Lingua tswana|sotho]]), ''Thuda'' ([[Lingua venda|venda]]) e ''Ndlulamithi'' ([[Lingua zulu|zulu]]) nell'Africa meridionale<ref name=walker/>.

==TaxonomyTassonomia anded evolutionevoluzione==

[[File:Shansitherium tafeli Beijing.jpg|thumb|left|MountedScheletro di ''[[Shansitherium]]'' skeletonal fromMuseo thedi [[BeijingStoria MuseumNaturale ofdi Natural History]]Pechino.]]

TheLa giraffegiraffa ise onel'[[Okapia ofjohnstoni|okapi]] onlysono twole livinguniche speciesspecie ofviventi theappartenenti alla famiglia familydei [[Giraffidae|Giraffidi]],. theIn otherpassato beingtale thefamiglia [[okapi]].era Themolto familypiù wasnumerosa, oncetanto muchche morene extensive,sono withstati overdescritti 10più fossildi 10 [[GenusGenere (tassonomia)|generageneri]] describedfossili. GiraffidsI Giraffidi fecero la loro prima firstcomparsa arosecirca 8 millionmilioni yearsdi agoanni (mya)fa, innell'Europa southcentro-centralmeridionale, Europedurante during theil [[Miocene]] epoch. TheLa superfamilysuperfamiglia dei [[Giraffoidea]], togethercosì withcome thela famiglia familydegli [[Antilocapridae|Antilocapridi]] (whoseil onlycui extantunico speciesrappresentante isattuale theè l'[[pronghornAntilocapra americana|antilocapra]]), evolvedsi fromevolvette thea extinctpartire familyda [[Palaeomerycidae]].rappresentanti della famiglia estinta dei Paleomericidi<ref name="Mitchell20003">{{cite journalCita pubblicazione| author autore= Mitchell, G.; Skinner, J. D. | year anno= 2003 | title titolo= On the origin, evolution and phylogeny of giraffes ''Giraffa camelopardalis'' | journal rivista= Transactions of the Royal Society of South Africa | volume = 58 | issue numero= 1| pages pp= 51–73| doi = 10.1080/00359190309519935| url = http://www.bringyou.to/GiraffeEvolution.pdf}}</ref>. TheIl earliestGiraffide knownconosciuto giraffidpiù wasantico theè deer-likeil ''[[Climacoceras]]'', dall'aspetto simile a un cervo.

WhileSebbene theil progressiveprogressivo elongationallungamento ofdi thecollo necke andarti limbssia canriscontrabile bein foundtutto throughoutil thelignaggio giraffiddei lineageGiraffidi, itè becamedivenuto morepiù pronouncedpronunciato in generageneri such ascome ''[[Giraffokeryx]]'', ''[[Palaeotragus]]'' (possiblepossibile ancestor of theantenato dell'okapi), ''[[Samotherium]]'' ande ''[[Bohlinia]]''.<ref name="Mitchell20003"/>. Il ''Bohlinia'', enteredin Chinaseguito andai northerncambiamenti Indiaclimatici, migrò in responseCina toe climatenell'India change.settentrionale, Fromdove here,sarebbe thecomparso genusil genere ''[[Giraffa]]'', evolvedche andsuccessivamente, aroundverso 7 myamilioni di anni fa, enteredsi trasferì in Africa. FurtherUlteriori climatemutamenti changesclimatici causedportarono thealla extinctionscomparsa ofdelle the Asiangiraffe giraffesasiatiche, whilementre thequelle Africanafricane onessopravvissero survivede anddettero radiatedvita into severala newnuove speciesspecie. ''G. camelopardalis'' arosecomparve aroundin 1Africa myaorientale incirca easternun Africamilione duringdi anni fa, thenel [[Pleistocene]].<ref name="Mitchell20003"/>. SomeAlcuni biologistsbiologi suggestsostengono thatche thel'attuale moderngiraffa giraffediscenda descended fromda ''[[Giraffa jumae|G. jumae]]'';<ref name=sim1996/>, othersmentre findaltri considerano un candidato più probabile ''[[Giraffa gracilis|G. gracilis]]'' a more likely candidate.<ref name="Mitchell20003"/>. ItSi isritiene believedche thatla thespinta mainprincipale driverper forl'evoluzione thedelle evolutiongiraffe ofsia thestato giraffesil wascambiamento theclimatico, changeiniziato from8 extensivemilioni forestsdi toanni morefa, che portò alla scomparsa opendelle habitatsforeste, whichsostituite beganda 8habitat mya.più aperti<ref name="Mitchell20003"/>. SomeAlcuni researchersricercatori havehanno hypothesizedipotizzato thatche thisun newnuovo habitatambiente withe anuove differentfonti dietalimentari, includingcome le foglie degli alberi del genere ''[[Acacia]]'', maypotrebbero haveaver exposedesposto giraffegli ancestorsantenati todella toxinsgiraffa thata causedtossine higherche mutationavrebbero ratesprovocato andun atasso highermaggiore ratedi ofmutazioni evolution.e, quindi, di spinta evolutiva<ref name="bada"/>.

TheLa giraffegiraffa wasfu oneuna ofdelle thenumerose manyspecie speciesdescritte firstper describedla byprima volta da [[Carl Linnaeus|Carlo Linneo]] innel 1758. HeEgli gavela itbattezzò thecon binomialil namenome binomiale di ''[[Cervus]] camelopardalis''. [[In seguito, nel 1772, Morten Thrane Brünnich]] classifiedistituì theil genusgenere ''Giraffa'' in 1772.<ref name="Dagg1971"/>. InAgli theinizi earlydel 19thXIX centurysecolo, [[Jean-Baptiste Lamarck]] believedcredette thatche theil giraffe'slungo longcollo neckdella wasgiraffa anfosse "acquireduna characteristic"«caratteristica acquisita», developedsviluppatasi asattraverso generationsgenerazioni ofdi ancestralgiraffe giraffesancestrali strivedche tosi reachsforzavano thedi leavesraggiungere ofle tallfoglie trees.degli alberi più alti<ref name="Prothero 2003"/>. ThisQuesta theoryteoria wasvenne in eventuallyseguito rejectedrifiutata, ande scientistsattualmente nowgli believescienziati thatspiegano thequesta giraffe'scaratteristica neckcon arosela throughteoria Darwiniandella [[naturalselezione selectionnaturale]]—that ancestraldarwiniana, giraffessecondo withla longquale necksle therebygiraffe hadancestrali acon competitivecolli advantagepiù thatlunghi bettererano enabledpiù themavvantaggiate todi reproducequelle andcon passcolli onpiù theircorti, genes.e avevano quindi maggiori probabilità di riprodursi e perpetuare i loro geni<ref name="Prothero 2003"/>.

===SubspeciesSottospecie===

[[File:Genetic subdivision in the giraffe based on mitochondrial DNA sequences.png|thumb|400px|right|"Approximate«Areali geographic rangesapprossimativi, furcolore patternsdel andmanto e relazioni [[phylogeneticsFilogenesi|phylogeneticfilogenetiche]] relationshipstra betweenalcune somesottospecie giraffedi subspeciesgiraffa basedbasate onsul sequenziamento del [[mitochondrial DNA mitocondriale]] sequences. ColoredI dotspunti oncolorati thesulla mapmappa representindicano samplingle localities.località Thedove phylogeneticè treestato iseffettuato ail campionamento. L'albero filogenetico è un [[maximum-likelihoodAlbero filogenetico|filogramma]] [[PhylogeneticMetodo tree#Specialdella treemassima typesverosimiglianza|phylogramdi massima verosimiglianza]] basedbasato onsu samplescampioni fromprelevati da 266 giraffesgiraffe. AsterisksGli alongasterischi brancheslungo correspondi torami corrispondono a valori [[Clade#Definitions|nodenodali]] valuesdi ofoltre more thanil 90% percentdi supporto [[Resampling (statistics)Ricampionamento|bootstrap]] support. StarsLe atstelle branchall'estremità tipsdei identifyrami identificano gli [[paraphyleticAplotipo|aplotipi]] [[haplotypeParafilia|parafiletici]]s foundriscontrati innelle Maasaigiraffe andmasai Reticulatede giraffes".reticolate»<ref name=GeneticStructure>{{citeCita journalpubblicazione|titletitolo=Extensive population genetic structure in the giraffe|authorautore=Brown, D. M.; Brenneman R. A.; Koepfli, K-P.; Pollinger, J. P.; Milá, B.; Georgiadis, N. J.; Louis Jr., E. E.; Grether, G. F.; Jacobs, D. K.; Wayne R. K.|journalrivista= BMC Biology |yearanno=2007|volume=5|issuenumero=1|pagep=57|doi=10.1186/1741-7007-5-57|pmc=2254591|pmid=18154651}}</ref>.]]

Attualmente vengono riconosciute ben nove sottospecie di giraffa (i dati sul numero di esemplari risalgono al 2010):

Up to nine subspecies of giraffe are recognized (with population estimates {{As of|2010|lc=y}}):

* ''[[NubianGiraffa giraffecamelopardalis camelopardalis|G. c. camelopardalis]]'', {{zoo|Linnaeus|1758}}<ref name= "MacDonald">{{CiteCita booklibro|authorautore=Pellow, R. A.|contributioncontributo=Giraffe and Okapi|yearanno=2001|titletitolo=The Encyclopedia of Mammals|editionedizione= 2nd|editorcuratore=MacDonald, D|publishereditore=Oxford University Press|pagespp=520–27|isbn=0-7607-1969-1}}</ref>, thela [[nominateSottospecie|sottospecie subspeciesnominale]], isè knownnota ascome thegiraffa della [[Nubia]]n giraffe. ItVive is found in easternnel [[SouthSudan del SudanSud]] andorientale south-westerne nell'[[EthiopiaEtiopia]] sud-occidentale. FewerSi thanpensa 250che arein thoughtnatura tone remainrimangano inmeno thedi 250 wildcapi, althoughma thisil numbernumero isesatto uncertain.è incerto<ref name=wildstatus>{{CiteCita web|url= http://www.giraffeconservation.org/giraffe_facts.php?pgid=40 |titletitolo= Giraffe – The Facts: Current giraffe status? |publishereditore=Giraffe Conservation Foundation |accessdateaccesso= 21 dicembre 2010-12-21}}</ref>. ItÈ ismolto rarerara in captivitycattività, althoughma aun groupgruppo isè keptattualmente atospitato [[Al Ainallo Zoo]] indi theAl Ain, negli [[UnitedEmirati ArabArabi EmiratesUniti]].<ref name='"Al Ain exhibits"'>{{citeCita web|titletitolo=Exhibits|url=http://www.awpr.ae/en/Visit/Pages/AfricanMixedExhibit.aspx|publishereditore=Al Ain Zoo|datedata=2003-02-25 febbraio 2003|accessdateaccesso= 2011-11-21 novembre 2011}}</ref>. InNel 2003, thisquesto groupgruppo numberedera formato da 14. esemplari<ref>{{CiteCita web|url=http://www.uaeinteract.com/docs/Nubian_giraffe_born_in_Al_Ain_zoo/6971.htm|titletitolo=Nubian giraffe born in Al Ain zoo|publishereditore=UAE Interact|accessdateaccesso=2010-12-21 dicembre 2010}}</ref>.

* ''[[ReticulatedGiraffa giraffecamelopardalis reticulata|G. c. reticulata]]'', {{zoo|De Winton|1899}}<ref name= "MacDonald"/>, knownnota ascome thegiraffa reticulatedreticolata<ref name= "MacDonald"/> oro della [[Horn ofCorno d'Africa|SomaliSomalia]] giraffe, isè nativeoriginaria to north-easterndel [[Kenya]] nord-orientale, southerndell'Etiopia Ethiopiameridionale ande della [[Somalia]]. ItSi isstima estimatedche thatin nonatura morenon thanne 5,000rimangano remainpiù indi the5000 wild,esemplari<ref name=wildstatus/>, andma basedsecondo oni [[Internationaldati Speciesdel InformationSistema System]]Internazionale records,d'Informazione moresulle thanSpecie ve ne sono più di 450 arenegli keptzoo indi zoos.tutto il mondo<ref name=ISIS>{{citeCita web|url=https://app.isis.org/abstracts/Abs77545.asp|titletitolo= Giraffa |publishereditore=[[International Species Information System|ISIS]]|yearanno=2010|accessdateaccesso= 4 novembre 2010-11-04}}</ref>

* ''[[AngolanGiraffa giraffecamelopardalis angolensis|G. c. angolensis]]'' {{zoo|Lydekker|1903}}, thela giraffa dell'[[Angola]]n oro della [[Namibia]]n giraffe, isè founddiffusa in northernnella Namibia settentrionale, south-westernnello [[Zambia]] sud-occidentale, in [[Botswana]] ande westernnello [[Zimbabwe]] occidentale. AUno studio genetico del 2009 geneticeffettuato studysu onmembri thisdi subspeciesquesta suggestssottospecie thatha therivelato northernche le popolazioni stanziate nelle regioni settentrionali del [[Namibdeserto Desertdel Namib]] ande nel [[Parco nazionale Etosha|Parco NationalNazionale Parkdi Etosha]] populations formapparterrebbero a separateuna subspecies.sottospecie separata<ref>{{citeCita journalpubblicazione|doi= 10.1111/j.1365-2028.2009.01078.x|authorautore= Brenneman, R. A.; Louis, E. E. Jr; Fennessy, J. |yearanno=2009|titletitolo=Genetic structure of two populations of the Namibian giraffe, ''Giraffa camelopardalis angolensis''|journalrivista=African Journal of Ecology|volume=47|issuenumero=4|pagespp=720–28}}</ref>. ItSi isstima estimatedche thatin nonatura morenon thanve 20,000ne remainsiano inpiù thedi wild;20.000 esemplari<ref name=wildstatus/>, andmentre approximatelynegli 20zoo aredi kepttutto inil zoos.mondo ne vengono ospitati circa 20 individui<ref name=ISIS/>.

* ''[[KordofanGiraffa giraffecamelopardalis antiquorum|G. c. antiquorum]]'', ({{zoo|Swainson|1835}})<ref name= "MacDonald"/>, la giraffa thedel [[Kordofan]] giraffe, hasha auna distributiondistribuzione whichche includescomprende southernil [[ChadCiad]] meridionale, thela [[CentralRepubblica African RepublicCentrafricana]], northernil [[CameroonCamerun]] andsettentrionale north-easterne la [[DemocraticRepubblica RepublicDemocratica of the Congo|DRdel Congo]] nord-orientale. PopulationsIn passato le popolazioni stanziate in CameroonCamerun werevenivano formerlyclassificate includedcome inappartenenti a ''G. c. peralta'', butma thistale wasvisione incorrect.si è rivelata incorretta<ref name=WestAfricaGiraffe>{{CiteCita journalpubblicazione|authorautore=Hassanin, A.; Ropiquet, A.; Gourmand, B-L.; Chardonnet, B.; Rigoulet, J.|yearanno=2007|titletitolo= Mitochondrial DNA variability in Giraffa camelopardalis: consequences for taxonomy, phylogeography and conservation of giraffes in West and central Africa|journalrivista=Comptes Rendus Biologies|volume=330|issuenumero=3|pagespp= 173–83|pmid= 17434121|doi=10.1016/j.crvi.2007.02.008}}</ref>. NoIn morenatura thannon 3,000ne arerimangono believedpiù todi remain3000 in the wild.capi<ref name=wildstatus/>. ConsiderableRiguardo confusionagli hasesemplari existedpresenti overin thecattività, statusè ofstato thisdifficile subspeciesvalutarne andil numero, data la confusione che si era creata con ''G. c. peralta''. inInfatti, zoos. Innel 2007, itè wasstato showndimostrato thatche alltutte allegedle ''G. c. peralta'' inospitate [[Listnegli ofzoo zoos#Europe|Europeaneuropei zoos]] were, in fact,erano ''G. c. antiquorum''.<ref name=WestAfricaGiraffe/>. WithDopo thiseventuali correctioncorrezioni, approximatelyil 65numero aredi keptesemplari in zoos.cattività è stato stimato sulle 65 unità<ref name=ISIS/>.

* ''[[MasaiGiraffa giraffetippelskirchi|G. c. tippelskirchi]]'', {{zoo|Matschie|1898}}<ref name= "MacDonald"/>, knownnota ascome thegiraffa [[Maasai people|Masaimasai]]<ref name= "MacDonald"/> oro del [[KilimanjaroKilimangiaro]] giraffe, canvive benelle foundregioni incentrali centrale andmeridionali southerndel Kenya ande in [[Tanzania]]. ItIn isnatura estimatednon thatne norimangono morepiù thandi 40,.000 remain in the wild,<ref name=wildstatus/> ande approximatelynegli 100zoo areve keptne insono zoos.circa 100 esemplari<ref name=ISIS/>.

* ''[[RothschildGiraffa giraffecamelopardalis rothschildi|G. c. rothschildi]]'' {{zoo|Lydekker|1903}}<ref name= "MacDonald"/> isè knownnota variouslycome asgiraffa thedi [[Lionel Walter Rothschild, 2nd Baron Rothschild|Rothschild]],<ref name= "MacDonald"/>, [[Lakedel Baringo|Baringo]] oro dell'[[Uganda]]n giraffe. ItsIl rangesuo includesareale partscomprende ofparte dell'Uganda ande del Kenya.<ref name=iucn/>. ItsLa presencesua inpresenza Southnel Sudan isdel uncertain.Sud è incerta<ref name=IUCNrothschildi>{{IUCN2008|assessors=Fennessy, J.; Brown, D.|year=2008|id=174469|title=Giraffa camelopardalis ssp. rothschildi|downloaded=2009-3-13}}</ref>. FewerSi thanritiene 700che arein believednatura tone remainrimangano inmeno thedi wild,700 capi<ref name=wildstatus/>, andma morenegli thanzoo 450ve arene keptsono inpiù zoos.di 450<ref name=ISIS/>.

* ''[[SouthGiraffa Africancamelopardalis giraffegiraffa|G. c. giraffa]]'' {{zoo|von Schreber|1784}}, thela giraffa del [[South AfricaSudafrica]]n giraffe, isè founddiffusa innel northernSudafrica South Africasettentrionale, southernnel Botswana meridionale, southernnello Zimbabwe andmeridionale south-westerne nel [[MozambiqueMozambico]] sud-occidentale. ItSi isstima estimatedche thatin nonatura morenon thanne 12,000rimangano remainpiù indi the wild,12.000<ref name=wildstatus/>, andma approximatelycirca 45 arecapi keptsono inospitati zoos.negli zoo di tutto il mondo<ref name=ISIS/>.

* ''[[RhodesianGiraffa giraffecamelopardalis thornicrofti|G. c. thornicrofti]]'', {{zoo|Lydekker|1911}}<ref name= "MacDonald"/>, calleddetta thegiraffa [[Harry Scottdi Thornicroft|Thornicroft]]<ref name= "MacDonald"/> oro della [[Rhodesia]]n giraffe, isvive restrictedunicamente to thenella [[Luangwa River(fiume)|Luangwavalle Valleydel Luangwa]], in easternnello Zambia orientale. NoNon morene thanrimangono 1,500più di 1500 remaincapi in the wild,natura<ref name=wildstatus/> withe nonenessun keptesemplare inè zoos.attualmente ospitato negli zoo<ref name=ISIS/>.

* ''[[WestGiraffa Africancamelopardalis giraffeperalta|G. c. peralta]]'', {{zoo|Thomas|1898}}<ref name= "MacDonald"/>, commonlynota knowncomunemente ascome thegiraffa Westdell'Africa African,occidentale<ref name= "MacDonald"/>, del [[Niger]] oro della [[Nigeria]]n giraffe,<ref name=IUCNperalta>{{IUCN2008|assessors=Fennessy, J.; Brown, D.|year=2008|id=136913|title=Giraffa camelopardalis ssp. peralta|downloaded=2012-03-05}}</ref>, isè [[EndemismEndemismo|endemicendemica]] to south-westerndel Niger. sud-occidentale<ref name=iucn/>. FewerIn thannatura 220ne individualsrimangono remainmeno indi the220 wild.esemplari<ref name=wildstatus/>. GiraffesIn inpassato Cameroonle weregiraffe formerlypresenti believedin toCamerun belongerano toconsiderate thisappartenenti subspeciesa questa sottospecie, butma areoggi actuallysi preferisce inserirle in ''G. c. antiquorum''.<ref name=WestAfricaGiraffe/>. ThisQuesto errorerrore resultedportò ina someuna confusioncerta overconfusione itsriguardo statusal innumero zoosdi esemplari ospitati negli zoo, butma innel 2007 itvenne wasstabilito establishedche thattutte allle "«''G. c. peralta''"» keptospitate innegli Europeanzoo zooseuropei actually areerano ''G. c. antiquorum''.<ref name=WestAfricaGiraffe/>.

[[File:Giraffe koure niger 2006.jpg|thumb|TheRarissima endangeredgiraffa Westdell'Africa African giraffeoccidentale.]]

Le varie sottospecie di giraffa si distinguono per l'aspetto del manto. Le giraffe reticolate e masai rappresentano due forme limite: le prime hanno macchie nettamente delineate, mentre le seconde hanno macchie dai contorni molto frastagliati<ref name=estes/>. Vi sono inoltre ulteriori differenze nella larghezza delle linee che separano tali macchie. La giraffa dell'Africa occidentale ha linee molto spesse, mentre nelle giraffe della Nubia e in quelle reticolate tali linee sono piuttosto sottili<ref name=Kingdon1988/>. La prima presenta inoltre una colorazione più chiara di tutte le altre sottospecie<ref name=Kingdon1988/>.

Giraffe subspecies are distinguished by their coat patterns. The reticulated and Masai giraffe represent two extremes of giraffe patch shapes. The former has neatly shaped patches while the latter has jagged ones.<ref name=estes/> There are also differences in the width of the lines separating the patches. The West African giraffe has thick lines while the Nubian and reticulated giraffe have thin ones.<ref name=Kingdon1988/>{{rp|321–22}} The former also has a lighter coat pelage than other subspecies.<ref name=Kingdon1988/>{{rp|322}}

ASecondo i risultati ottenuti nel corso di uno studio del 2007 studyeffettuato onsulla thegenetica geneticsdi ofsei sixsottospecie subspecies—the- Westle giraffe dell'Africa Africanoccidentale, di Rothschild, reticulatedreticolate, Masaimasai, Angolandell'Angola ande Southdel AfricanSudafrica giraffe—suggests-, thatqueste theyultime mayandrebbero inclassificate factcome bespecie separate. species.Sulla Thebase studydel deducedgrado fromdi [[geneticderiva driftgenetica]] inriscontrata [[nuclearnel DNA|nuclear]] andnucleare e [[mitochondrial DNA mitocondriale|mitocondriale]] (mtDNA), thatgli giraffesstudiosi fromhanno thesededotto populationsche arele [[Reproductivegiraffe isolation|reproductivelyappartenenti isolated]]a queste popolazioni sono isolate da un punto di vista riproduttivo e si accoppiano tra andloro rarelysolo interbreedraramente, evenperfino thoughquando nonon naturalvi obstaclesè blockalcun theirostacolo mutualnaturale access.a frapporsi tra esse<ref name=GeneticStructure/>, Thiscome includesnel adjacentcaso populationsdelle ofgiraffe di Rothschild, reticulatedreticolate ande Masai giraffesmasai. TheLa Masaisottospecie giraffenota maycome alsogiraffa consistmasai ofpotrebbe ainoltre fewessere speciescostituita separatedda byvarie thespecie [[Eastseparate Africandalla Rift|Rift Valley]]. ReticulatedLe andgiraffe Masaireticolate giraffese havemasai thepresentano highestla mtDNAmaggiore diversity,diversità whichnel isDNA consistentmitocondriale, withdovuta theal factfatto thatche giraffesla originatedspecie inha easternavuto origine nell'Africa orientale. PopulationsLe furtherpopolazioni northsettentrionali evolveddiscendono fromdalle theprime, formermentre whilequelle thosemeridionali todalle theseconde. southSembra evolvedche fromle thegiraffe latter.scelgano Giraffespartner appearche topresentano selectlo matesstesso oftipo thedi samemanto, coatsulla type,base whichdi areuna imprintedsorta ondi them''imprinting'' asche calves.si sviluppa quando sono in tenera età<ref name=GeneticStructure/>. TheLe implicationsconseguenze ofdi thesequesta findingsscoperta forsulla theconservazione conservationdelle ofgiraffe giraffessono werestate summarisedriassunte byda David Brown, leadautore authorprincipale ofdello thestudio, con queste studyparole, whorilasciate toldal [[BBC News]]: "Lumping«Raggruppare alltutte giraffesle intogiraffe onein speciesun'unica obscuresspecie thenasconde realityil thatfatto someche kindsalcune offorme giraffeparticolari aresono onsull'orlo the brinkdell'estinzione. SomeAlcune ofdi thesequeste populationspopolazioni numbersono onlycostituite ada fewpoche hundredcentinaia individualsdi andesemplari neede immediatenecessitano protection."di una protezione immediata»<ref>{{CiteCita news|publishereditore=BBC News|titletitolo=Not one but 'six giraffe species'|authorautore= Lever, A-M.|datedata=2007-12-21 dicembre 2007|url=http://news.bbc.co.uk/1/hi/sci/tech/7156146.stm |accessdateaccesso=4 marzo 2009-03-04}}</ref>.

La giraffa dell'Africa occidentale è più strettamente imparentata con le giraffe di Rothschild e con quelle reticolate che con la giraffa del Kordofan. I suoi antenati potrebbero essere migrati dall'Africa orientale a quella settentrionale, per poi essere stati spinti più a sud dall'avanzare del deserto del Sahara. Al massimo della sua estensione, il [[lago Ciad]] potrebbe aver costituito una barriera tra le giraffe dell'Africa occidentale e quelle del Kordofan nel corso dell'[[Olocene]]<ref name=WestAfricaGiraffe/>.

The West African giraffe is more closely related to the Rothchild and reticulated giraffe than to the Kordofan giraffe. Its ancestor may have migrated from eastern to northern Africa and then to its current range with the development of the Sahara desert. At its largest, [[Lake Chad]] may have acted as a barrier between West African and Kordofan giraffes during the [[Holocene]].<ref name=WestAfricaGiraffe/>

==AppearanceDescrizione ande anatomyanatomia==

[[File:Giraffe08 - melbourne zoo.jpg|thumb|Primo piano della testa di un esemplare allo [[Zoo di Melbourne]].]]

{{commons cat|Category:Giraffa camelopardalis anatomy}}

[[File:Giraffe08Giraffe - melbourne zooskeleton.jpg|thumb|thumb|CloseupScheletro ofdi thegiraffa headal ofMuseo adi giraffeOsteologia at thedi [[MelbourneOklahoma ZooCity]].]]

Nel pieno dello sviluppo la giraffa misura 5-6 m di altezza; i maschi sono più alti delle femmine<ref name="Dagg1971">{{Cita pubblicazione|autore=Dagg, A. I.|anno=1971|titolo=Giraffa camelopardalis|rivista=Mammalian Species|volume=5|pp=1–8|url=http://www.science.smith.edu/msi/pdf/i0076-3519-005-01-0001.pdf|doi=10.2307/3503830|numero=5}}</ref>. Il peso medio è di 1600 kg nei maschi adulto e di 830 kg nelle femmine adulte<ref name="Skinner1990">{{Cita libro|autore=Skinner, J. D.; Smithers, R. H. M.|anno=1990|titolo=The mammals of the southern African subregion|pp=616–20|editore=University of Pretoria|isbn=0-521-84418-5}}</ref>. Malgrado il collo e le zampe molto lunghi, la giraffa ha un corpo relativamente corto<ref name=anatomy/>. Posti ai lati della testa, gli occhi, grandi e sporgenti, consentono una buona visione dei dintorni, data anche l'altezza alla quale si trovano<ref name=Williams/>. La giraffa vede a colori<ref name=Williams/> e ha, inoltre, udito e [[olfatto]] molto sviluppati<ref name="Prothero 2003"/>. Grazie a una serie di muscoli, è in grado di chiudere le narici per difendersi da tempeste di sabbia e formiche<ref name=Williams/>. La lingua prensile è lunga circa 50 cm. Di colore nero-violaceo, forse come difesa dalle scottature dei raggi del sole, viene utilizzata per brucare il fogliame, nonché per il ''grooming'' e la pulizia del naso<ref name=Williams/>. Anche il labbro superiore è prensile e viene utilizzato ugualmente per strappare le foglie dai rami. Le labbra, la lingua e l'interno della bocca sono ricoperte da [[Papilla linguale|papille]] che proteggono queste strutture dalle punture delle spine<ref name="Dagg1971"/>.

[[File:Giraffe skeleton.jpg|thumb|Giraffe skeleton on display at the [[Museum of Osteology]], [[Oklahoma City, Oklahoma]]]]

[[File:Giraffa camelopardalis reticulata-atTobuZoo-2012.ogv|thumb|(video)Coppia Adi pairgiraffe ofallo giraffesZoo atdi [[Tobu Zoo]], in [[Saitama prefecture|Saitama]], Japan(Giappone).]]

Fully grown giraffes stand {{convert|5|–|6|m|abbr=on}} tall, with males taller than females.<ref name="Dagg1971">{{Cite journal|author=Dagg, A. I.|year=1971|title=Giraffa camelopardalis|journal= Mammalian Species|volume=5|pages=1–8|url= http://www.science.smith.edu/msi/pdf/i0076-3519-005-01-0001.pdf|doi=10.2307/3503830|issue=5}}</ref> The average weight is {{convert|1600|kg|lb|abbr=on}} for an adult male and {{convert|830|kg|lb|abbr=on}} for an adult female.<ref name="Skinner1990">{{Cite book|author=Skinner, J. D.; Smithers, R. H. M.|year=1990|title=The mammals of the southern African subregion|pages=616–20|publisher=University of Pretoria|isbn=0-521-84418-5}}</ref> Despite its long neck and legs, the giraffe's body is relatively short.<ref name=anatomy/>{{rp|66}} Located at both sides of the head, the giraffe's large, bulging eyes give it good all-round vision from its great height.<ref name=Williams/>{{rp|25}} Giraffes see in color<ref name=Williams/>{{rp|26}} and their senses of hearing and [[olfaction|smell]] are also sharp.<ref name="Prothero 2003"/> The animal can close its muscular nostrils to protect against sandstorms and ants.<ref name=Williams/>{{rp|27}} The giraffe's [[prehensile]] tongue is about {{convert|50|cm|in|abbr=on}} long. It is purplish-black in color, perhaps to protect against sunburn, and is useful for grasping foliage as well as for grooming and cleaning the animal's nose.<ref name=Williams/>{{rp|27}} The upper lip of the giraffe is also prehensile and useful when foraging. The lips, tongue and inside of the mouth are covered in [[Taste bud|papillae]] to protect against thorns.<ref name="Dagg1971"/>

[[File:Giraffa camelopardalis reticulata-atTobuZoo-2012.ogv|thumb|(video) A pair of giraffes at [[Tobu Zoo]], in [[Saitama prefecture|Saitama]], Japan.]]

TheIl manto coatè hasricoperto darkda blotcheschiazze oro patchesmacchie (whichche canpossono beessere orangedi colore arancione, [[ChestnutCastagno (colorcolore)|chestnutcastano]], brownmarrone oro nearlyquasi black on colornero<ref name="Prothero 2003"/>) separatedseparate byda lightpeli hairchiari (usuallygeneralmente whitebianchi oro color [[CreamCrema (colourcolore)|creamcrema]] in color<ref name="Prothero 2003"/>). MaleIl giraffesmanto becomedei darkermaschi asdiviene theypiù age.scuro con l'età<ref name=estes>{{CiteCita booklibro|titletitolo=The Behavior Guide to African Mammals: including Hoofed Mammals, Carnivores, Primates|authorautore=Estes, R.|publishereditore=University of California Press|pagespp=202–07|yearanno=1992|isbn=0-520-08085-8}}</ref>. TheIl manto chiazzato coatha patternuna servesfunzione asdi [[camouflagecamuffamento]], allowinge itconsente toall'animale blenddi inmimetizzarsi thetra lightle andzone shadedi patternsluce ofe savannaombra woodlands.tipiche della savana arbustiva<ref name="Mitchell20003"/><ref name= "MacDonald"/>. TheLa skinpelle underneathal thedi darksotto areasdelle mayaree servescure aspotrebbe windowsavere foranche una funzione di [[thermoregulationtermoregolazione]], beingdal sitesmomento forche complexospita bloodnumerosi vesselcapillari systemssanguigni ande largegrosse sweatghiandole glands.sudoripare<ref name=Mitchell2004>{{CiteCita journalpubblicazione|authorautore=Mitchell, G.; Skinner, J.D.|yearanno=2004|titletitolo=Giraffe thermoregulation: a review|journalrivista=Transactions of the Royal Society of South Africa: Proceedings of a Colloquium on Adaptations in Desert Fauna and Flora|volume=59|issuenumero=2|pagespp=49–57|issn=0035-919X|url=http://www.sabinet.co.za/abstracts/royalsa/royalsa_v59_n2_a13.html|doi=10.1080/00359190409519170}}</ref>. EachCiascun individualindividui giraffeha hasuna adisposizione uniquedelle coatmacchie pattern.unica<ref name=estes/>. TheLa skinpelle ofdella agiraffa giraffeè isdi mostlycolore gray.prevalentemente grigio<ref name="Skinner1990"/>. ItÈ isanche alsopiuttosto thickspessa, ande allowsl'animale themè toquindi runin throughgrado thorndi bushcorrere withoutrapidamente beingtra punctured.la boscaglia senza ferirsi con le spine della vegetazione<ref name=Williams/>{{rp|34}}. TheirIl furmanto maypuò servefungere asda a chemicaldifesa defencechimica, asdato itche isè fullimpregnato ofdi parasitesostanze repellentsrepellenti thatper givei theparassiti animalche aconferiscono characteristicall'animale scentun odore caratteristico. ThereNel aremantello atvi leastsono elevenalmeno mainundici [[aromaticity|aromatic]]sostanze chemicalschimiche inaromatiche theprincipali, fur,sebbene l'odore tipico althoughsia dovuto soprattutto all'[[indoleindolo]] ande al [[Scatolo|3-methylindolemetilindolo]] are responsible for most of the smell. BecausePoiché thei malesmaschi havehanno aun strongerodore odorpiù thanpungente thedelle femalesfemmine, itsi isritiene suspectedche thatesso itabbia alsoanche hasuna afunzione sexual function.sessuale<ref>{{CiteCita journalpubblicazione|authorautore=Wood, W. F.; Weldon, P. J.|yearanno=2002|titletitolo=The scent of the reticulated giraffe (''Giraffa camelopardalis reticulata'')|journalrivista=Biochemical Systematics and Ecology|volume=30|issuenumero=10|pagespp=913–17|doi=10.1016/S0305-1978(02)00037-6}}</ref>. AlongLungo theil collo animaldell'sanimale neckcorre isuna acriniera manecostituita madeda ofbrevi short,peli erect hairs.eretti<ref name="Dagg1971"/>. TheLa {{convert|1|m|ft|abbr=on}}coda, taillunga endsun metro, termina in aun long,ciuffo darkdi tuftpeli oflunghi haire andscuri, ise usedviene asusata aper defensescacciare againstgli insects.insetti<ref name=Williams/>{{rp|36}}.

===SkullCranio ande ossiconesossiconi===

BothEntrambi sexesi havesessi prominentpossiedono horn-likeprominenti structuresstrutture calledsimili a corna dette [[ossiconeossiconi]]s, whichcostituite are formed from ossifiedda [[cartilagetessuto cartilagineo]], coveredossificato inricoperto skinda anduno fusedstrato todi thepelle, skullfuse atcon theil cranio all'altezza delle [[parietalOsso boneparietale|ossa parietali]]s.<ref name=estes/>. BeingEssendo [[vascular]]izedvascolarizzati, thegli ossiconesossiconi maypotrebbero havegiocare aun roleruolo innella thermoregulation.termoregolazione<ref name=Mitchell2004/>, Ossiconesma arevengono alsoutilizzati usedanche innei combatcombattimenti betweentra males.maschi<ref name="sim2010"/>. AppearanceIl isloro aaspetto reliableè guideutile toper thedeterminare sexil orsesso ageo ofl'età adi giraffe:un thedeterminato ossiconesesemplare: ofgli femalesossiconi anddi youngfemmine aree thingiovani andsono displaysottili tuftse ofpresentano hairciuffi ondi toppelo all'estremità, whereasmentre thosequelli ofdei adultmaschi malesadulti endterminano incon knobsuna andsorta tenddi toprotuberanza bee baldtendono ona top.essere privi di pelo all'estremità<ref name=estes/>. ThereSulla isparte alsoanteriore adel mediancranio lump,vi whichè isanche moreuna prominentsorta indi malesprominenza mediana, at the frontpiù ofpronunciata thenei [[skull]].maschi<ref name="Dagg1971"/>. MalesI developmaschi sviluppano depositi di [[calciumCalcio (elemento)|calcio]] depositsche thatcon forml'avanzare bumpsdell'età onformano theirdelle skullsspecie asdi theybernoccoli age.sul cranio<ref name="Prothero 2003"/>. AIl giraffe'scranio skulldella isgiraffa lightenedè byalleggerito multipleda [[Sinusuna serie (anatomy)|sinuses]].di seni<ref name=anatomy/>{{rp|70}}. HoweverTuttavia, asnei malesmaschi ageadulti, theiril skullscranio becomediviene heavierpiù andpesante, moree club-like,nel helpingcorso themdei becomecombattimenti moreviene dominantimpiegato income combat.una mazza<ref name=estes/>. TheLa uppermascella jawsuperiore haspresenta a groovedun [[palatepalato]] andscanalato lacksed frontè teeth.priva dei denti frontali<ref name=Williams/>{{rp|26}}. The giraffe'sI [[Molar (tooth)|molarmolari]]s havehanno auna roughersuperficie surfacepiù thanruvida thosedi ofquella somedella othermaggior mammals.parte degli altri mammiferi<ref name=Williams/>{{rp|27}}.

===LegsZampe, locomotionlocomozione ande posturepostura===

TheLe frontzampe andanteriori backe legsposteriori ofdella agiraffa giraffehanno areall'incirca approximatelyla thestessa same lengthlunghezza. TheIl [[RadiusRadio (boneanatomia)|radiusradio]] ande l'[[ulna]] ofdelle thezampe frontanteriori legssono arearticolate articulated by thedal [[carpuscarpo]], whichche, whilesebbene structurallysia equivalentuna tostruttura theequivalente humanal wristpolso umano, functionsfunziona ascome aun knee.ginocchio<ref>{{citeCita booklibro|authorautore=MacClintock, D.; Mochi, U.|yearanno=1973|titletitolo=A natural history of giraffes|publishereditore=Scribner|pagep=30|isbn=0-684-13239-7}}</ref>. TheIl footpiede ofraggiunge thei giraffe30 reachescm adi diameterdiametro, ofe {{convert|30|cm|in|abbr=on}},lo andzoccolo theè [[hoof]]alto is15 {{convert|15|cm|in|abbr=on}} highnei inmaschi malese and10 {{convert|10|cm|in|abbr=on}} innelle females.femmine<ref name=Williams/>{{rp|36}}. TheLa rearparte ofposteriore eachdi hoofogni iszoccolo lowè andbassa thee [[fetlock]]i isnodelli closesono tovicini theal groundsuolo, allowingsì da thepermettere footal topiede supportdi thesostenere animal'smeglio weight.il peso dell'animale<ref name="Dagg1971"/>. GiraffesLe lackgiraffe [[dewclaw]]ssono andprive interdigitaldi glands.speroni Thee giraffeghiandole interdigitali. L'sosso pelvispelvico, thoughsebbene relativelyrelativamente shortcorto, hasha anun [[Iliumosso (bone)|iliumiliaco]] thatallungato isalle outspreadestremità at the upper ends.superiori<ref name="Dagg1971"/>.

ALa giraffegiraffa hasha onlydue twosoli [[gait]]s:tipi walkingdi andandatura: galloping.il Walkingpasso ise doneil bygaloppo. movingMentre thecammina, legsmuove oncon oneambedue sidele ofzampe the body at the same timedell'uno, thenpoi doingcon theambedue samequelle ondell'altro thelato, other side.simultaneamente<ref name=estes/>. WhenQuando gallopinggaloppa, themuove hindle legszampe moveposteriori aroundattorno thea frontquelle legsanteriori beforeprima theche latterqueste moveultime forward,si spostino in avanti<ref name="Prothero 2003"/> ande thetiene tailla willcoda curl up.raggomitolata<ref name=estes/>. TheL'animale animalsi reliesaffida ona themovimenti forwardavanti ande backwardindietro motionsdella oftesta itse headdel andcollo neckper tomantenere maintainl'equilibrio balancee andil thecontro-momento counterdurante momentumil while galloping.galoppo<ref name=Kingdon1988/>{{rp|327–29}}. La Thegiraffa giraffepuò canraggiungere reachpunte adi sprintvelocità speeddi of60 up to {{convert|60|km/h|abbr=on}},<ref>{{CiteCita journalpubblicazione| last cognome= Garland | first nome= T | coauthors coautori= Janis, C. M. | year anno= 1993 | title titolo= Does metatarsal/femur ratio predict maximal running speed in cursorial mammals? | url = http://www.biology.ucr.edu/people/faculty/Garland/GarlandJanis1993.pdf | journal rivista= Journal of Zoology | volume = 229 | issue numero= 1 | pages pp= 133–51 | doi = 10.1111/j.1469-7998.1993.tb02626.x }}</ref> ande canmantenere sustainun'andatura di {{convert|50| km/h|abbr=on}} forper severalalcuni kilometers.chilometri<ref>{{CiteCita booklibro|authorautore=Rafferty, John. P|yearanno=2011|titletitolo=Grazers (Britannica Guide to Predators and Prey)|publishereditore=Britannica Educational Publishing|pagep=194|isbn=1-61530-336-7|postscript=<!-- Bot inserted parameter. Either remove it; or change its value to "." for the cite to end in a ".", as necessary. -->{{inconsistent citations}}}}</ref>.

AQuando girafferiposa, restsla bygiraffa lyingsorregge withil itscorpo bodysulle onzampe top of its folded legs.ripiegate<ref name=Kingdon1988>{{CiteCita booklibro|authorautore=Kingdon, J. |yearanno=1988|titletitolo=East African Mammals: An Atlas of Evolution in Africa, Volume 3, Part B: Large Mammals|pagespp=313–37|publishereditore=University Of Chicago Press |isbn=0-226-43722-1}}</ref>{{rp|329}}. ToPer lie downsdraiarsi, thel'animale animalsi kneelsinginocchia onsulle itszampe frontanteriori legse andpoi thenabbassa lowersil theresto restdel of its bodycorpo. To get backPer uprialzarsi, itsposta firstavanti getsle onginocchia itse kneesdistende andle spreadszampe itsposteriori hindper legssollevare to raise itsle hindquartersanche. ItIn thenseguito straightensdistende itsle frontzampe legsanteriori. WithA eachogni steppasso, thel'animale animalfa swingsoscillare itsla head.testa<ref name=Williams/>{{rp|31}}. TheLa giraffegiraffa sleepsdorme intermittently aroundper 4.,6 hoursore peral daygiorno, mostlysoprattutto atdi night.notte, ad intervalli<ref name=sleep/>. ItGeneralmente usuallydorme sleepsdistesa, lyingma down,alcuni howeveresemplari, standingspecialmente sleepsquelli havepiù been recordedanziani, particularlysono instati oldervisti dormire in individualspiedi. IntermittentDurante shortle "deepbrevi sleep"fasi phasesintermittenti whiledi lying«sonno areprofondo», characterizedquando byè thedistesa, giraffela bendinggiraffa itsripiega neckil backwardscollo ande restingpoggia itsla headtesta onsull'anca theo hipsulla orcoscia; thigh,gli astudiosi positionritengono believedche toquesta indicateposizione indichi i periodi di [[paradoxicalRapid sleepeye movement|sonno paradosso]].<ref name=sleep>{{citeCita journalpubblicazione|lastcognome=Tobler, I.; Schwierin, B.|titletitolo=Behavioural sleep in the giraffe (''Giraffa camelopardalis'') in a zoological garden|yearanno=1996|journalrivista=Journal of Sleep Research|volume=5|issuenumero=1|pagespp=21–32|doi=10.1046/j.1365-2869.1996.00010.x|first1nome1=I.|last2cognome2=Schwierin|first2nome2=B.|pmid=8795798}}</ref>. IfSe thela giraffegiraffa wantsvuole toinchinarsi bend down toper drinkbere, it either spreads its front legs or bends its knees.<ref name=estes/> Giraffes would probably not be competent swimmers as their long legs would be highly cumbersome in the water,<ref name = "swim">{{cite journalCita pubblicazione| doi = 10.1016/j.jtbi.2010.04.007 | author autore= Henderson, D. M.; Naish, D. | year anno= 2010 | title titolo= Predicting the buoyancy, equilibrium and potential swimming ability of giraffes by computational analysis | url = | journal rivista= Journal of Theoretical Biology | volume = 265 | issue numero= 2| pages pp= 151–59 | pmid = 20385144 }}</ref> although they could possibly float.<ref name="Naish">{{Cite magazine| last = Naish | first = D. | author-link = Darren Naish |date= January 2011 | year = 2011| title = Will it Float? | periodical = [[Scientific American]] | issn = 0036-8733 | volume = 304 | issue = 1 | page = 22| url = http://www.scientificamerican.com/article.cfm?id=will-it-float}}</ref> When swimming, the thorax would be weighed down by the front legs, making it difficult for the animal to move its neck and legs in harmony<ref name = "swim"/><ref name="Naish"/> or keep its head above the surface.<ref name = "swim"/>

===Neck===

[[File:Flickr - Rainbirder - High-rise living.jpg|thumb|left|An adult male giraffe feeding high up on an acacia]]

The giraffe has an extremely elongated neck, which can be up to {{convert|2|m|abbr=on}} in length, accounting for much of the animal's vertical height.<ref name=Williams/>{{rp|29}} The long neck results from a disproportionate lengthening of the [[cervical vertebrae]], not from the addition of more vertebrae. Each cervical vertebra is over {{convert|28|cm|in|abbr=on}} long.<ref name=anatomy>{{citeCita booklibro|authorautore=Swaby, S.|yearanno=2010|contributioncontributo=Giraffe|editorcuratore=Harris, T.|titletitolo=Mammal Anatomy: An Illustrated Guide|publishereditore=Marshall Cavendish Corporation|pagespp=64–84|isbn=0-7614-7882-5}}</ref>{{rp|71}} They comprise 52–54 percent of the length of the giraffe's [[vertebral column]], compared with the 27–33 percent typical of similar large ungulates, including the giraffe’s closest living relative, the [[okapi]].<ref name=bada>{{Cite journalCita pubblicazione| doi = 10.1111/j.1096-3642.2008.00458.x | last cognome= Badlangana | first nome= L. N. | coauthors coautori= Adams, J. W.; Manger P. R. | title titolo= The giraffe ''(Giraffa camelopardalis)'' cervical vertebral column: A heuristic example in understanding evolutionary processes? | journal rivista= Zoological Journal of the Linnean Society | volume = 155 | issue numero= 3 | pages pp= 736–57 | year anno= 2009}}</ref> This elongation largely takes place after birth, as giraffe mothers would have a difficult time giving birth to young with the same neck proportions as adults.<ref name=van>{{Cite journalCita pubblicazione| doi = 10.1002/jez.b.21353 | last cognome= Van Sittert | first nome= S. J. | coauthors coautori= Skinner, J. D.; Mitchell, G. | title titolo= From fetus to adult – An allometric analysis of the giraffe vertebral column | journal rivista= Journal of Experimental Zoology Part B Molecular and Developmental Evolution | volume = 314B | issue numero= 6 | pages pp= 469–79 | year anno= 2010}}</ref> The giraffe's head and neck are held up by large muscles and a [[nuchal ligament]], which are anchored by long dorsal spines on the anterior [[thoracic vertebrae]], giving the animal a hump.<ref name="Dagg1971"/>

The giraffe's neck vertebrae have [[ball and socket joint]]s.<ref name=anatomy/>{{rp|71}} In particular, the [[Atlas (anatomy)|atlas]]&ndash;[[Axis (anatomy)|axis]] joint (C1 and C2) allows the animal to tilt its head vertically and reach more branches with the tongue.<ref name=Williams/>{{rp|29}} The point of articulation between the cervical and thoracic vertebrae of giraffes is shifted to lie between the first and second thoracic vertebrae (T1 and T2), unlike most other ruminants where the articulation is between the seventh cervical vertebra (C7) and T1.<ref name=bada/><ref name=van/> This allows C7 to contribute directly to increased neck length and has given rise to the suggestion that T1 is actually C8, and that giraffes have added an extra cervical vertebra.<ref>{{CiteCita journalpubblicazione|authorautore=Solounias, N.|yearanno=1999|titletitolo=The remarkable anatomy of the giraffe's neck|journalrivista=Journal of Zoology|volume=247|issuenumero=2|pagespp=257–68|doi=10.1111/j.1469-7998.1999.tb00989.x|url=http://www.ikhebeenvraag.be/mediastorage/FSDocument/73/download.pdf}}</ref> However, this proposition is not generally accepted, as T1 has other morphological features, such as an articulating [[rib]], deemed diagnostic of thoracic vertebrae, and because exceptions to the mammalian limit of seven cervical vertebrae are generally characterized by increased [[neurological disorder|neurological anomalies]] and maladies.<ref name=bada/>

There are two main hypotheses regarding the evolutionary origin and maintenance of elongation in giraffe necks.<ref name=sim2010>{{Cite journalCita pubblicazione| doi = 10.1111/j.1469-7998.2010.00711.x | last cognome= Simmons | first nome= R. E.| coauthors coautori= Altwegg, R. | title titolo= Necks-for-sex or competing browsers? A critique of ideas on the evolution of giraffe | journal rivista= Journal of Zoology | volume = 282 | issue numero= 1 | pages pp= 6–12 | year anno= 2010}}</ref> The "competing [[browsing (predation)|browsers]] hypothesis" was originally suggested by [[Charles Darwin]] and only challenged recently. It suggests that competitive pressure from smaller browsers, such as [[kudu]], [[steenbok]] and [[impala]], encouraged the elongation of the neck, as it enabled giraffes to reach food that competitors could not. This advantage is real, as giraffes can and do feed up to {{convert|4.5|m|abbr=on}} high, while even quite large competitors, such as kudu, can only feed up to about {{convert|2|m|abbr=on}} high.<ref name=dt1990>{{Cite journalCita pubblicazione| doi = 10.1111/j.1365-2028.1990.tb01136.x | last cognome= du Toit | first nome= J. T. | title titolo= Feeding-height stratification among African browsing ruminants | journal rivista= African Journal of Ecology | volume = 28 | issue numero= 1 | pages pp= 55–62 | year anno= 1990 | url = http://courses.biology.utah.edu/goller/7406/Goller7406/duToitPdfs/Feedingheightstrat_1990.pdf}}</ref> There is also research suggesting that browsing competition is intense at lower levels, and giraffes feed more efficiently (gaining more leaf biomass with each mouthful) high in the canopy.<ref>{{CiteCita journalpubblicazione|authorautore= Cameron, E. Z.; du Toit, J. T. | title titolo= Winning by a Neck: Tall Giraffes Avoid Competing with Shorter Browsers| journal rivista= American Naturalist | volume = 169| issue numero= 1| pages pp= 130–35| year anno= 2007| doi = 10.1086/509940 |pmid= 17206591 |url= http://www.cnr.usu.edu/files/uploads/faculty/winning_by_a_neck-du_Toit.pdf}}</ref><ref>{{CiteCita journalpubblicazione|authorautore= Woolnough, A. P.; du Toit, J. T. | title titolo= Vertical zonation of browse quality in tree canopies exposed to a size-structured guild of African browsing ungulates| journal rivista= Oecologia | volume = 129| issue numero= 1| pages pp= 585–90| year anno= 2001| doi = 10.1007/s004420100771|url=http://courses.biology.utah.edu/goller/7406/Goller7406/duToitPdfs/Verticalzonation_2001.pdf}}</ref> However, scientists disagree about just how much time giraffes spend feeding at levels beyond the reach of other browsers,<ref name=sim1996/><ref name=sim2010/><ref name=dt1990/><ref name=sexdiff>{{CiteCita journalpubblicazione|doi= 10.1111/j.1439-0310.1991.tb01190.x |authorautore= Young, T. P.; Isbell, L. A. | title titolo= Sex differences in giraffe feeding ecology: energetic and social constraints| journal rivista= Ethology | volume = 87| issue numero= 1–2| pages pp= 79–89| year anno= 1991 |dio = 10.1007/s004420100771|url=http://tpyoung.ucdavis.edu/publications/1991GiraffesEthology.pdf}}</ref>

and a 2010 study found that adult giraffes with longer necks actually suffered higher mortality rates under drought conditions than their shorter-necked counterparts. This study suggests that maintaining a longer neck requires more nutrients, which puts longer-necked giraffes at risk during a food shortage.<ref name="demography">{{citeCita journalpubblicazione|authorautore=Mitchell, G.; van Sittert, S.; Skinner, J. D.|yearanno=2010|titletitolo=The demography of giraffe deaths in a drought|journalrivista=Transactions of the Royal Society of South Africa|volume=65|issuenumero=

3|pagespp=165–68|doi=10.1080/0035919X.2010.509153}}</ref>

The other main theory, the [[sexual selection]] hypothesis, proposes that the long necks evolved as a secondary [[sexual dimorphism|sexual characteristic]], giving males an advantage in "necking" contests (see below) to establish dominance and obtain access to sexually receptive females.<ref name=sim1996>{{CiteCita journalpubblicazione|authorautore=Simmons, R. E.; Scheepers, L. | title titolo= Winning by a Neck: Sexual Selection in the Evolution of Giraffe| journal rivista= The American Naturalist| volume = 148| issue numero= 5| pages pp= 771–86| year anno= 1996|url=http://bill.srnr.arizona.edu/classes/182/Giraffe/WinningByANeck.pdf|doi=10.1086/285955}}</ref> In support of this theory, necks are longer and heavier for males than females of the same age,<ref name=sim1996/><ref name=sim2010/> and the former do not employ other forms of combat.<ref name=sim1996/> However, one objection is that it fails to explain why female giraffes also have long necks.<ref>{{CiteCita journalpubblicazione|authorautore= Mitchell, G.; van Sittert, S. J.; Skinner, J. D. | title titolo= Sexual selection is not the origin of long necks in giraffes| journal rivista= Journal of Zoology | volume = 278| issue numero= 4| pages pp= 281–86| year anno= 2009| doi=10.1111/j.1469-7998.2009.00573.x}}</ref>

{{-}}

===Internal systems===

[[File:Flickr - Rainbirder - Reticulated Giraffe drinking.jpg|thumb|Giraffe bending down to drink. The animal's rete mirabile prevents excess blood flow to the brain when the neck is lowered.]]

In mammals, the left [[recurrent laryngeal nerve]] is longer than the right; in the giraffe it is over {{convert|30|cm|in|abbr=on}} longer. These nerves are longer in the giraffe than in any other living animal;<ref name="Wedel">{{CiteCita journalpubblicazione|authorautore=Wedel, M. J.|yearanno=2012|titletitolo=A monument of inefficiency: the presumed course of the recurrent laryngeal nerve in sauropod dinosaurs|journalrivista=Acta Palaeontologica Polonica|volume=57|issuenumero=2|pagespp=251–56|doi=10.4202/app.2011.0019|url=http://www.app.pan.pl/archive/published/app57/app20110019.pdf}}</ref> the left nerve is over {{convert|2|m|abbr=on}} long.<ref>{{citeCita booklibro|authorautore=Harrison, D. F. N.|yearanno=1995|titletitolo=The Anatomy and Physiology of the Mammalian Larynx|publishereditore=Cambridge University Press|pagep=165|isbn=0-521-45321-6}}</ref> Each nerve cell in this path begins in the [[brainstem]] and passes down the neck along the [[vagus nerve]], then branches off into the recurrent laryngeal nerve which passes back up the neck to the larynx. Thus, these nerve cells have a length of nearly {{convert|5|m|abbr=on}} in the largest giraffes.<ref name="Wedel"/> The structure of a giraffe's brain resembles that of domestic cattle.<ref name=Williams/>{{rp|31}} The shape of the skeleton gives the giraffe a small lung volume relative to its mass.<ref name=SkinnerJD2011>{{CiteCita journalpubblicazione|authorautore=Skinner, J. D.; Mitchell, G.|yearanno= 2011|titletitolo= Lung volumes in giraffes, ''Giraffa camelopardalis''|journalrivista= Comparative Biochemistry and Physiology – Part A: Molecular & Integrative Physiology|volume= 158|issuenumero= 1|pagespp= 72–78|doi= 10.1016/j.cbpa.2010.09.003|url= http://137.215.9.22/bitstream/handle/2263/16472/Mitchell_Lung(2011).PDF?sequence=1}}</ref> Its long neck gives it a large amount of [[Dead space (physiology)|dead space]], in spite of its narrow windpipe. These factors increase the resistance to airflow. Nevertheless, the animal can still supply enough oxygen to its tissues.<ref name=SkinnerJD2011/>

The [[circulatory system]] of the giraffe has several adaptations for its great height. Its heart, which can weigh more than {{convert|25|lb|kg|abbr=on}} and measures about {{convert|2|ft|cm|abbr=on}} long, must generate approximately double the blood pressure required for a human to maintain blood flow to the brain.<ref name="Prothero 2003"/> Giraffes have unusually high heart rates for their size, at 150 beats per minute.<ref name=anatomy/>{{rp|76}} In the upper neck, the [[rete mirabile]] prevents excess blood flow to the brain when the giraffe lowers its head.<ref name= "MacDonald"/> The [[jugular vein]]s also contain several (most commonly seven) valves to prevent blood flowing back into the head from the [[inferior vena cava]] and [[right atrium]] while the head is lowered.<ref>{{citeCita journalpubblicazione|doi=10.3957/056.039.0210|authorautore=Mitchell, G.; van Sittert, S. J.; Skinner, J. D.|titletitolo=The structure and function of giraffe jugular vein valves|journalrivista= South African Journal of Wildlife Research|volume=39|issuenumero=2|pagespp=175–80|url=http://137.215.9.22/bitstream/handle/2263/13994/Mitchell_Structure(2009).pdf?sequence=1 |yearanno=2009}}</ref> Conversely, the blood vessels in the lower legs are under great pressure (because of the weight of fluid pressing down on them). To solve this problem, the skin of the lower legs is thick and tight; preventing too much blood from pouring into them.<ref name= "MacDonald"/>

Giraffes have [[Esophagus|oesophageal muscles]] that are unusually strong to allow regurgitation of food from the stomach up the neck and into the mouth for [[wikt:ruminate|rumination]].<ref name=anatomy/>{{rp|78}} They have four chambered stomachs, as in all ruminants, and the first chamber has adapted to their specialized diet.<ref name="Dagg1971"/> The giraffe's intestines measure up to {{convert|80|m|ft|abbr=on}} in length<ref name="Dagg1971"/> and have a relatively small ratio of small to large intestine.<ref>{{cite journalCita pubblicazione| author autore= Pérez, W.; Lima, M.; Clauss, M. | year anno= 2009 | title titolo= Gross anatomy of the intestine in the giraffe (''Giraffa camelopardalis'') | url = | journal rivista= Anatomia, Histologia, Embryologia | volume = 38 | issue numero= 6| pages pp= 432–35 | pmid = 19681830 | doi=10.1111/j.1439-0264.2009.00965.x}}</ref> The liver of the giraffe is small and compact.<ref name=anatomy/>{{rp|76}} A gallbladder is generally present during fetal life, but it may disappear before birth.<ref name="Dagg1971"/><ref>{{cite journalCita pubblicazione| authorautore=Cave, A. J. E. | titletitolo=On the liver and gall-bladder of the Giraffe | journalrivista=Proceedings of the Zoological Society of London | volume=120 | pagespp=381–93 | yearanno=1950 | doi=10.1111/j.1096-3642.1950.tb00956.x | issuenumero=2}}</ref><ref>{{cite journalCita pubblicazione| author1autore1=Oldham-Ott, Carla K. |author2autore2=Gilloteaux, Jacques | titletitolo=Comparative morphology of the gallbladder and biliary tract in vertebrates: variation in structure, homology in function and gallstones | journalrivista=Microscopy Research and Technique | volume=38 | issuenumero=6 | pagespp=571–79 | yearanno=1997 | doi=10.1002/(SICI)1097-0029(19970915)38:6<571::AID-JEMT3>3.0.CO;2-I}}</ref>

==Behavior and ecology==

===Habitat and feeding===

[[File:Giraffe feeding, Tanzania.jpg|thumb|Giraffe extending its tongue to feed. Its tongue, lips and palate are tough enough to deal with sharp thorns in trees.]]

Giraffes usually inhabit [[savanna]]s, [[grassland]]s and open [[woodland]]s. They prefer ''[[Acacia]]'', ''[[Commiphora]]'', ''[[Combretum]]'' and open ''[[Terminalia (plant)|Terminalia]]'' woodlands over denser environments like ''[[Brachystegia]]'' woodlands.<ref name=Kingdon1988/>{{rp|322}} The Angolan giraffe can be found in desert environments.<ref>{{cite thesis |author=Fennessy, J.|year=2004 |title=Ecology of desert-dwelling giraffe ''Giraffa camelopardalis angolensis'' in northwestern Namibia|publisher=[[University of Sydney]] |degree=[[Doctor of Philosophy|Ph.D.]] |url=http://ses.library.usyd.edu.au/handle/2123/910}}</ref> Giraffes browse on the twigs of trees, preferring trees of genera ''Acacia'', ''Commiphora'' and ''Terminalia'',<ref name=kingdon>{{CiteCita booklibro|titletitolo=The Kingdon Field Guide to African Mammals|authorautore=Kingdon, J.|publishereditore=Academic Press|pagespp=339–44|yearanno=1997|isbn=0-12-408355-2}}</ref> which are important sources of calcium and protein to sustain the giraffe's growth rate.<ref name="Mitchell20003"/> They also feed on shrubs, grass and fruit.<ref name=Kingdon1988/>{{rp|324}} A giraffe eats around {{convert|34|kg|lb|abbr=on}} of foliage daily.<ref name=estes/> When stressed, giraffes may chew the bark off branches. Although [[herbivorous]], the giraffe has been known to visit carcasses and lick dried meat off bones.<ref name=Kingdon1988/>{{rp|325}}

During the wet season, food is abundant and giraffes are more spread out, while during the dry season, they gather around the remaining evergreen trees and bushes.<ref name=kingdon/> Mothers tend to feed in open areas, presumably to make it easier to detect predators, although this may reduce their feeding efficiency.<ref name=sexdiff /> As a [[ruminant]], the giraffe first chews its food, then swallows it for processing and then visibly passes the half-digested cud up the neck and back into the mouth to chew again.<ref name=anatomy/>{{rp|78-79}} It is common for a giraffe to salivate while feeding.<ref name=Williams/>{{rp|27}} The giraffe requires less food than many other herbivores, because the foliage it eats has more concentrated nutrients and it has a more efficient digestive system.<ref name=kingdon/> The animal's feces come in the form of small pellets.<ref name="Dagg1971"/> When it has access to water, a giraffe drinks at intervals no longer than three days.<ref name=estes/>

Riga 138 ⟶ 137:

[[File:Giraffa camelopardalis angolensis (mating).jpg|thumb|left|Male giraffe mounting a female. Only dominant males are generally able to mate.]]

===Social life and breeding habits===

While giraffes are usually found in groups, the composition of these groups tends to be open and ever-changing.<ref name=Manyara>{{CiteCita journalpubblicazione|authorautore= van der Jeugd, H. P; Prins, H. H. T. | title titolo= Movements and group structure of giraffe (''Giraffa camelopardalis'') in Lake Manyara National Park, Tanzania| journal rivista= Journal of Zoology | volume = 251| issue numero= 1| pages pp= 15–21| year anno= 2000| doi=10.1111/j.1469-7998.2000.tb00588.x|url=http://www.resource-ecology.org/publ/2000_Jeugd,Prins_MovementsAndGroupStructureOfGiraffeInLakeManyara.pdf}}</ref> They have few strong social bonds, and aggregations usually change members every few hours. For research purposes, a "group" has been defined as "a collection of individuals that are less than a kilometre apart and moving in the same general direction."<ref name= "Pratt 1985">{{cite journalCita pubblicazione| doi = 10.1080/00222938500770471 | author autore= Pratt D. M.; Anderson V. H. | year anno= 1985 | title titolo= Giraffe social behavior | journal rivista= Journal of Natural History | volume = 19 | issue numero= 4 | pages pp= 771–81 }}</ref> The number of giraffes in a group can range up to 32 individuals.<ref name=Manyara/> The most stable giraffe groups are those made of mothers and their young,<ref name= "Pratt 1985"/> which can last weeks or months.<ref name= "Leuthold 1979"/> Social cohesion in these groups is maintained by the bonds formed between calves.<ref name=Kingdon1988/>{{rp|330}}<ref name= "Pratt 1985"/> Mixed-sex groups made of adult females and young males are also known to occur.<ref name= "Pratt 1985"/> Subadult males are particularly social and will engage in playfights. However, as they get older males become more solitary.<ref name= "Leuthold 1979"/<ref name= "Leuthold 1979"/> Giraffes are not territorial,<ref name="Dagg1971"/> but they have [[home range]]s.<ref name=estes/> Male giraffes occasionally wander far from areas that they normally frequent.<ref name=Kingdon1988/>{{rp|329}}

Reproduction is broadly polygamous: a few older males mate with the fertile females. Male giraffes assess female fertility by tasting the female's urine to detect [[estrus]], in a multi-step process known as the [[Flehmen response]].<ref name= "Pratt 1985"/><ref name= "Leuthold 1979">{{CiteCita journalpubblicazione|authorautore=Leuthold, B. M.|yearanno=1979|titletitolo=Social organization and behaviour of giraffe in Tsavo East National Park|journalrivista=African Journal of Ecology|volume=17|issuenumero=1|pagespp=19–34|doi=10.1111/j.1365-2028.1979.tb00453.x}}</ref> Males prefer young adult females over juveniles and older adults.<ref name= "Pratt 1985"/> Once an estrous female is detected, the male will attempt to court her. When courting, dominant males will keep subordinate ones at bay.<ref name= "Leuthold 1979"/> During copulation, the male stands on its hind legs with its head held up and its front legs resting on the female's sides.<ref name=estes/>

Although generally quiet and non-vocal, giraffes have been heard to communicate using various sounds. During courtship, males emit loud coughs.<ref name=estes/> Females call their young by bellowing. Calves will emit snorts, bleats, mooing and mewing sounds. Giraffes also snore, hiss, moan and make flute-like sounds,<ref name=estes/> and they communicate over long distances using [[infrasound]].<ref>{{citeCita web|titletitolo=Silent Sentinels?|publishereditore=PBS online – Nature|url=http://www.pbs.org/wnet/nature/episodes/tall-blondes/silent-sentinels/2256/|accessdateaccesso=2011-12-21 dicembre 2011}}</ref>

===Birthing and parental care===

[[File:Giraffe Family.jpg|thumb||Mother giraffe and calves feeding. It is mostly the females that raise young, and they may gather in nursery herds.]]

Giraffe [[gestation]] lasts 400–460 days, after which a single calf is normally born, although twins occur on rare occasions.<ref name=ap>{{CiteCita web|titletitolo=Mammal Guide – Giraffe|publishereditore=[[Animal Planet]]|url=http://animal.discovery.com/guides/mammals/habitat/tropgrassland/giraffe.html|accessdateaccesso=7 marzo 2009-03-07}}</ref> The mother gives birth standing up. The calf emerges head and front legs first, having broken through the [[fetal membrane]]s, and falls to the ground, severing the [[umbilical cord]].<ref name="Dagg1971"/> The mother then grooms the newborn and helps it stand up.<ref name=Williams/>{{rp|40}} A newborn giraffe is about {{convert|1.8|m|ft|abbr=on|sigfig=1}} tall. Within a few hours of birth, the calf can run around and is almost indistinguishable from a one-week-old. However, for the first 1–3 weeks, it spends most of its time hiding;<ref name="Langman 1977">{{CiteCita journalpubblicazione|authorautore=Langman, V. A.|yearanno=1977|titletitolo=Cow-calf relationships in giraffe (''Giraffa camelopardalis giraffa'')|journalrivista=Zeitschrift fur Tierpsychologie|volume=43|issuenumero=3|pagespp=264–86}} [[Digital object identifier|doi]]:[http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.1977.tb00074.x/abstract 10.1111/j.1439-0310.1977.tb00074.x]</ref> its coat pattern providing camouflage. The ossicones, which have lain flat while it was in the womb, become erect within a few days.<ref name=estes/>

Mothers with calves will gather in nursery herds, moving or browsing together. Mothers in such a group may sometimes leave their calves with one female while they forage and drink elsewhere. This is known as a "calving pool".<ref name= "Langman 1977"/> Adult males play almost no role in raising the young,<ref name=Kingdon1988/>{{rp|337}} although they appear to have friendly interactions.<ref name= "Pratt 1985"/> Calves are at risk of predation, and a mother giraffe will stand over her calf and kick at an approaching predator.<ref name=estes/> Females watching calving pools will only alert their own young if they detect a disturbance, although the others will take notice and follow.<ref name= "Langman 1977"/> The bond a mother shares with her calf varies, though it can last until her next calving.<ref name= "Langman 1977"/> Likewise, calves may suckle for only a month<ref name=Kingdon1988/>{{rp|335}} or as long as a year.<ref name=estes/><ref name= "Leuthold 1979"/> Females become sexually mature when they are four years old, while males become mature at four or five years. However, males must wait until they are at least seven years old to gain the opportunity to mate.<ref name=estes/><ref name=Williams/>{{rp|40}}

Riga 154 ⟶ 153:

Male giraffes use their necks as weapons in combat, a behavior known as "necking". Necking is used to establish dominance and males that win necking bouts have greater reproductive success.<ref name=sim1996/> This behavior occurs at low or high intensity. In low intensity necking, the combatants rub and lean against each other. The male that can hold itself more erect wins the bout.<ref name=estes/> In high intensity necking, the combatants will spread their front legs and swing their necks at each other, attempting to land blows with their ossicones. The contestants will try to dodge each other's blows and then get ready to counter. The power of a blow depends on the weight of the skull and the arc of the swing.<ref name=estes/> A necking duel can last more than half an hour, depending on how well matched the combatants are.<ref name=Kingdon1988/>{{rp|331}}

After a duel, it is common for two male giraffes to caress and court each other, leading up to mounting and climax. Such interactions between males have been found to be more frequent than heterosexual coupling.<ref>{{CiteCita journalpubblicazione|authorautore=Coe, M. J.|yearanno=1967|titletitolo='Necking' behavior in the giraffe|journalrivista=Journal of Zoology|volume=151|issuenumero=2|pagespp=313–21|doi= 10.1111/j.1469-7998.1967.tb02117.x}}</ref> In one study, up to 94 percent of observed mounting incidents took place between males. The proportion of same-sex activities varied from 30–75 percent. Only one percent of same-sex mounting incidents occurred between females.<ref>{{CiteCita booklibro|authorautore=Bagemihl, B.|yearanno= 1999|titletitolo=Biological Exuberance: Animal Homosexuality and Natural Diversity| publishereditore=St. Martin's Press| pagespp=391–93|isbn= 0-312-19239-8}}</ref>

===Mortality and health===

<!-- [[File:Lioness_with_giraffe_kill,_jackal_lurking,_kenya,_august_9th_2012.jpg|thumb|right|Lioness seen with adult giraffe kill]] -->

Giraffes have an unusually long lifespan compared to other ruminants,<ref>{{CiteCita journalpubblicazione|authorautore=Müller, D.W.; Zerbe, P; Codron, D; Clauss, M; Hatt, J.M.|yearanno=2011|titletitolo=A long life among ruminants: giraffids and other special cases|journalrivista=Schweizer Archiv für Tierheilkunde|volume=153|issuenumero=11|pagespp=515–519|pmid=22045457|doi=10.1024/0036-7281/a000263}}</ref> up to 25 years in the wild.<ref name= "MacDonald"/> Because of their size, eyesight and powerful kicks, adult giraffes are usually not subject to predation.<ref name=estes/> However, they can fall prey to [[lion]]s and are regular prey for them in [[Kruger National Park]].<ref>{{CiteCita journalpubblicazione|authorautore=Owen-Smith, N.; Mills, M. G.|yearanno=2008|titletitolo= Predator-prey size relationships in an African large-mammal food web|journalrivista=Journal of Animal Ecology|volume=77|issuenumero=1|pagespp= 173–83|pmid= 18177336|url= http://137.215.9.22/bitstream/handle/2263/9023/Owen-Smith_Predator-prey(2008).pdf?sequence=1|doi=10.1111/j.1365-2656.2007.01314.x}}</ref> [[Nile crocodile]]s can also be a threat to giraffes when they bend down to drink.<ref name=Williams/>{{rp|31}} Calves are much more vulnerable than adults, and are additionally preyed on by [[leopard]]s, [[spotted hyena]]s and [[Lycaon pictus|wild dogs]].<ref name="Prothero 2003"/> A quarter to a half of giraffe calves reach adulthood.

Some parasites feed on giraffes. They are often hosts for [[tick]]s, especially in the area around the genitals, which has thinner skin than other areas.<ref name="Dagg1971"/> Tick species that commonly feed on giraffes are those of genera ''[[Hyalomma]]'', ''[[Amblyomma]]'' and ''[[Rhipicephalus]]''. Giraffes may rely on [[Red-billed Oxpecker|red-billed]] and [[yellow-billed oxpecker]]s to clean them of ticks and alert them to danger. Giraffes host numerous species of internal parasite and are susceptible to various diseases. They were victims of the (now eradicated) viral illness [[rinderpest]].<ref name="Dagg1971"/>

Riga 165 ⟶ 164:

===Cultural significance===

[[File:Giraffe cave art.jpg|thumb|Bushman rock art in Namibia depicting a giraffe]]

Humans have interacted with giraffes for millennia. The [[Bushmen]] of southern Africa have medicine dances named after some animals; the giraffe dance is performed to treat head ailments.<ref>{{CiteCita booklibro|authorautore=Ross, K.|yearanno=2003|titletitolo=Okavango: jewel of the Kalahari|publishereditore=Struik|pagep=168|isbn=1-86872-729-7}}</ref> How the giraffe got its height has been the subject of various African [[folktales]],<ref name=sim1996/> including one from eastern Africa which explains that the giraffe grew tall from eating too many magic herbs.<ref>{{citeCita booklibro|authorautore=Greaves, N.; Clement, R.|yearanno=2000|titletitolo=When Hippo Was Hairy: And Other Tales from Africa|publishereditore=Struik|pagespp=86–88|isbn=1-86872-456-5}}</ref> Giraffes were depicted in art throughout the African continent, including that of the [[Kiffian culture|Kiffians]], [[Ancient Egypt|Egyptians]] and [[Meroë|Meroë Nubians]].<ref name=Williams>{{CiteCita booklibro|authorautore=Williams, E.|yearanno=2011|titletitolo=Giraffe|publishereditore=Reaktion Books|isbn=1-86189-764-2}}</ref>{{rp|45–47}} The Kiffians were responsible for a life-size rock engraving of two giraffes that has been called the "world's largest rock art petroglyph".<ref name=Williams/>{{rp|45}}<ref>{{CiteCita web|url=http://www.bradshawfoundation.com/giraffe/|titletitolo=The Dabous Giraffe rock art petrograph|publishereditore=The Bradshaw Foundation|accessdateaccesso=6 novembre 2011-11-06}}</ref> The Egyptians gave the giraffe its own [[Egyptian hieroglyphs|hieroglyph]], named 'sr' in [[Old Egyptian language|Old Egyptian]] and 'mmy' in later periods.<ref name=Williams/>{{rp|49}} They also kept giraffes as pets and shipped them around the [[Mediterranean]].<ref name=Williams/>{{rp|48–49}}

[[File:Yongle-Giraffe1Tribute Giraffe with Attendant.jpg|thumb|left|Painting of a giraffe imported to China during the Ming Dynasty]]

The giraffe was also known to the [[Ancient Greece|Greeks]] and [[Ancient Rome|Romans]], who believed that it was an unnatural hybrid of a [[camel]] and a leopard and called it ''camelopardalis''.<ref name=Williams/>{{rp|50}} The giraffe was among the many animals collected and displayed by the Romans. The first one in Rome was brought in by [[Julius Caesar]] in 46 BC and exhibited to the public.<ref name=Williams/>{{rp|52}} With the [[fall of the Roman Empire]], the housing of giraffes in Europe declined.<ref name=Williams/>{{rp|54}} During the [[Middle Ages]], giraffes were only known to Europeans through contact with the Arabs, who revered the giraffe for its peculiar appearance.<ref name="Prothero 2003">{{CiteCita booklibro|authorautore=Prothero, D. R.; Schoch, R. M.|yearanno=2003|titletitolo=Horns, Tusks, and Flippers: The Evolution of Hoofed Mammals|publishereditore=Johns Hopkins University Press|pagespp=67–72|isbn=0-8018-7135-2}}</ref>

In 1414, a giraffe was shipped from [[Malindi]] to [[Bengal]]. It was then taken to China by explorer [[Zheng He]] and placed in a [[Ming Dynasty]] zoo. The animal was a source of fascination for the Chinese people, who associated it with the mythical [[Qilin]].<ref name=Williams/>{{rp|56}} The [[Medici giraffe]] was a giraffe presented to [[Lorenzo de' Medici]] in 1486. It caused a great stir on its arrival in Florence,<ref>{{CiteCita journalpubblicazione|pdf=http://www.archive.org/download/ErikRingmaraudienceForAGiraffeEuropeanExceptionalismAndTheQuest_744/ErikRingmarAudienceForAGiraffe.pdf |titletitolo=Audience for a Giraffe: European Expansionism and the Quest for the Exotic|authorautore= Ringmar, E.|journalrivista= Journal of World History| year anno= 2006| volume = 17| issue numero= 4| pages pp= 353–97 |jstor = 20079397|doi=10.1353/jwh.2006.0060}}</ref> being reputedly the first living giraffe to be seen in Italy since antiquity. Another [[Giraffe given to Charles X of France by Muhammad Ali of Egypt|famous giraffe]] was brought from Egypt to Paris in the early 19th century. A sensation, the giraffe was the subject of numerous memorabilia or "giraffanalia".<ref name=Williams/>{{rp|81}}

Giraffes continue to have a presence in modern culture. [[Salvador Dalí]] depicted them with [[conflagration|conflagrated]] manes in some of his surrealist paintings. Dali considered the giraffe to be a symbol of masculinity, and a flaming giraffe was meant to be a "masculine cosmic apocalyptic monster".<ref name=Williams/>{{rp|123}} Several children's books feature the giraffe, including David A. Ufer's ''The Giraffe Who Was Afraid of Heights'', [[Giles Andreae]]'s ''Giraffes Can't Dance'' and [[Roald Dahl]]'s ''[[The Giraffe and the Pelly and Me]]''. Giraffes have appeared in animated films, as minor characters in [[Disney]]'s ''[[The Lion King]]'' and ''[[Dumbo]]'', and in more prominent roles in ''[[The Wild]]'' and in the ''[[Madagascar (franchise)|Madagascar]]'' films. [[Sophie the Giraffe]] has been a popular [[teether]] since 1961. Another famous fictional giraffe is the Toys "R" Us mascot [[Toys "R" Us#Geoffrey the Giraffe|Geoffrey the Giraffe]].<ref name=Williams/>{{rp|127}} The giraffe is also the [[national animal]] of Tanzania.<ref>{{Cite bookCita libro|titletitolo=East Africa: Kenya, Tanzania & Uganda |authorautore=Knappert, J |authorlinkwkautore=Jan Knappert |yearanno=1987 |publishereditore=Vikas Publishing House|isbn= 0-7069-2822-9 |pagep=57}}</ref>

The giraffe has also been used for some scientific experiments and discoveries. Scientists have looked at the properties of giraffe skin when developing suits for astronauts and fighter pilots.<ref name=anatomy/>{{rp|76}} This is because the people in these professions are in danger of passing out if blood rushes to their legs. Computer scientists have modeled the coat patterns of several subspecies using [[reaction-diffusion|reaction–diffusion]] mechanisms.<ref>{{CiteCita journalpubblicazione|authorautore=Walter, M.; Fournier, A.; Menevaux, D.|yearanno=2001|titletitolo= Integrating shape and pattern in mammalian models in SIGGRAPH '01|journalrivista=Proceedings of the 28th annual conference on Computer graphics and interactive techniques|pagespp= 317–26 |doi= 10.1145/383259.383294|url =http://www.csun.edu/~renzo/GraphicsResources/Articles/walter.pdf|isbn=1-58113-374-X}}</ref> The [[constellation]] of [[Camelopardalis]], introduced in the seventeenth century, depicts a giraffe.<ref name=Williams/>{{rp|119–20}}

===Exploitation and conservation status===

Riga 179 ⟶ 178:

Giraffes were probably common targets for hunters throughout Africa.<ref name=Kingdon1988/>{{rp|337}} Different parts of their bodies were used for different purposes.<ref name="Dagg1971"/> Their meat was used for food. The tail hairs served as [[flyswatter]]s, bracelets, necklaces and thread.<ref name=Kingdon1988/>{{rp|337}}<ref name="Dagg1971"/> Shields, sandals and drums were made using the skin, and the strings of musical instruments were from the tendons.<ref name="Dagg1971"/> The smoke from burning giraffe skins was used by the medicine men of [[Buganda]] to treat nose bleeds.<ref name=Kingdon1988/>{{rp|337}} In the 19th Century, European explorers begin hunting them for sport.<ref name=Williams/>{{rp|129}} Habitat destruction has hurt the giraffe, too: in the [[Sahel]], the need for firewood and grazing room for livestock has led to [[deforestation]]. Normally, giraffes can coexist with livestock, since they do not directly compete with them.<ref name= "MacDonald"/>

The giraffe species as a whole is assessed as [[Least Concern]] from a conservation perspective by the [[International Union for Conservation of Nature|IUCN]], as it is still numerous. However, giraffes have been [[extirpated]] from much of their historic range including [[Eritrea]], [[Guinea]], [[Mauritania]] and [[Senegal]]. They may also have disappeared from [[Angola]], [[Mali]], and [[Nigeria]], but have been introduced to [[Rwanda]] and [[Swaziland]].<ref name=iucn/> Two subspecies, the [[West African giraffe]] and the [[Rothschild giraffe]], have been classified as [[Endangered species|Endangered]],<ref name=IUCNrothschildi/><ref name=IUCNperalta/> as wild populations of each of them number in the hundreds.<ref name=wildstatus/> In 1997, [[Jonathan Kingdon]] suggested that the [[Nubian giraffe]] was the most threatened of all giraffes;<ref name=kingdon/> {{as of|2010|lc=y}}, it may number fewer than 250, although this estimate is uncertain.<ref name=wildstatus/> Private game reserves have contributed to the preservation of giraffe populations in southern Africa.<ref name= "MacDonald"/> [[Giraffe Manor]] is a popular hotel in [[Nairobi]] which also serves a sanctuary for Rothschild's giraffes.<ref>{{citeCita web|authorautore=Lord. M|datedata=2012-01-11 gennaio 2012|titletitolo=Outlandish Outposts: Giraffe Manor in Kenya|publishereditore=Forbes.com|accessdateaccesso=4 aprile 2012-04-04|url=http://www.forbes.com/sites/forbestravelguide/2012/01/11/outlandish-outposts-giraffe-manor-in-kenya/}}</ref> The giraffe is a protected species in most of its range. In 1999, it was estimated that over 140,000 giraffes existed in the wild, but estimates in 2010 indicate that fewer than 80,000 remain.<ref name=wildstatus/>

===Note===