Elk na Irish

The **Irish elk** ( ***Megaloceros giganteus*** ),   kuma ana kiransa **katuwar barewa** ko **dan Irish**, wani nau'in barewa ne da ba a taɓa gani ba a cikin jinsin *Megaloceros* kuma yana daya daga cikin mafi girma da aka taɓa rayuwa. Yankinsa ya mamaye arewacin Eurasia a lokacin Pleistocene, daga Ireland (inda aka san shi daga yawancin ragowar da aka samu a cikin bogs) zuwa tafkin Baikal a Siberiya . Ragowar jinsunan na baya-bayan nan shine radiocarbon da aka yi kwanan watan kimanin shekaru 7,700 da suka gabata a yammacin Rasha.   Its tururuwa, wanda zai iya tsawon  fadin su ne mafi girma da aka sani na kowane barewa.  Ba ya da alaƙa da ko wane nau'in halittu da ake kira elk, tare da yarda cewa danginsa na kusa su ne barewa ( *Dama* ).    

## Taxonomy

### Tarihin bincike

Likitan ɗan ƙasar Irish Thomas Molyneux ne ya yi bayanin farko na kimiyya game da ragowar dabbar a shekara ta 1695, wanda ya gano manyan tururuwa daga Dardistown - waɗanda galibi ana gano su a Ireland - a matsayin na ƙwaya (wanda aka fi sani da moose a Arewacin Amirka), yana ƙarasa da cewa ta taɓa yin yawa a tsibirin.  An fara kiran shi da sunan *Alce gigantea* ta Johann Friedrich Blumenbach a cikin *Handbuch der Naturgeschichte* a cikin 1799,  tare da *Alce* kasancewar bambancin *Alces*, sunan Latin don elk. Asalin bayanin Blumenbach na *Alce gigantea* yana ba da taƙaitaccen bayani game da nau'in, yana ƙayyadaddun kawai cewa wannan nau'in "burbushin burbushin" ya fito ne daga Ireland kuma yana da girman girman jiki. A cewar Blumenbach,  nisa tsakanin kololuwar manyan tururuwa na iya kaiwa  . Wannan musamman fasalin da Blumenbach ya ambata ya ba da izini ga Roman Croitor don gano nau'in samfurin ƙaton barewa  wanda aka kwatanta kuma aka bayyana a karon farko a Louthiana na Thomas Wright .  Holotype na *Megaloceros giganteus* (Blumenbach, 1799) wani kwanyar namiji ne mai kyau wanda aka kiyaye shi tare da manyan tururuwa na musamman da aka samu a kewayen Dunleer ( County Louth, Ireland ).  A halin yanzu ana fallasa nau'in samfurin ƙaton barewa a Barmeath Castle inda Thomas Wright ya fara gani kuma ya bayyana shi. 

Masanin kimiyya dan kasar Faransa Georges Cuvier ya rubuta a shekara ta 1812 cewa dan kasar Irish ba ya cikin kowane nau'in dabbobi masu shayarwa a halin yanzu, yana bayyana shi " *le plus célèbre de tous les ruminans burbushin halittu* " (wanda ya fi shahara a cikin dukkanin burbushin halittu).  A cikin 1827 Joshua Brookes, a cikin jerin tarin tarin dabbobinsa, ya sanya wa sabon jinsin suna *Megaloceros* (wanda aka rubuta *Megalocerus* a bugu na farko) a cikin nassi mai zuwa:  

Etymology daga Girkanci :   "mai girma" +   "kaho, antler".  Nau'in kuma kawai nau'in mai suna a cikin bayanin shine *Megaloceros antiquorum*, bisa ga Irish ragowar yanzu ana la'akari da shi na *M. giganteus*, wanda ya sa tsohon ya zama ƙaramin junior . Adrian Lister yayi la'akari da ainihin bayanin a cikin 1987 don rashin isa ga ma'anar haraji.  A cikin 1828 Brookes ya buga jerin faɗaɗa a cikin nau'i na kasida don gwanjo mai zuwa, wanda ya haɗa da kalmar Latin " *Cornibus deciduis palmatis"* (ma'ana" tururuwa na dabino") a matsayin bayanin ragowar. The 1828 bugu da aka amince da International Commission on Zoological Nomenclature (ICZN) a 1977 a matsayin samuwan bugu don tushen zoological nomenclature.  Adrian Lister a cikin 1987 ya yanke hukunci cewa "lokacin " *Cornibus deciduis palmatis"* ya ƙunshi ma'anar da ta isa a ƙarƙashin  Ka'idar Zoological Nomenclature ta Duniya  (lashi na 12) don tabbatar da *Megalocerus* ."  Asalin rubutun *Megalocerus* ba a taɓa yin amfani da shi ba bayan fitowar ta ta asali. 

A cikin 1844, Richard Owen ya ambaci wani ma'anar ma'anar ɗan Irish elk, gami da shi a cikin sabon sunan subgenus *Megaceros*, *Cervus* ( *Megaceros* ) *hibernicus* . An ba da shawarar cewa za a samo wannan daga wani ƙaramin ma'ana na ɗan Irish elk wanda J. Hart ya bayyana a cikin 1825, *Cervus megaceros* .  Duk da kasancewar ƙaramin ma'ana, *Megaloceros* ya kasance a cikin duhu kuma *Megaceros* ya zama sunan gama gari na taxon.  Haɗin " *Megaceros giganteus"* an yi amfani da shi ta 1871.  George Gaylord Simpson a 1945 ya sake farfado da ainihin sunan *Megaloceros*, wanda ya zama ci gaba da amfani da shi, har sai wani yanke shawara na haraji a 1989 ta ICZN ya tabbatar da fifikon *Megaloceros* akan *Megaceros*, kuma *Megalo* spelling.  

Kafin karni na 20, elk na Irish, wanda ya samo asali daga ƙananan kakanni tare da ƙananan tururuwa, an ɗauke shi a matsayin babban misali na orthogenesis (juyin halitta wanda aka jagoranci), tsarin juyin halitta wanda ya sabawa juyin halitta na Darwiniyanci wanda nau'in nau'in jinsin da ke cikin zuriyarsu ke ƙara gyaggyarawa a hanya guda maras karkata, juyin halitta yana tafiya a cikin madaidaiciyar layin zaɓi na zaɓi na halitta . An yi iƙirarin cewa Orthogenesis ya haifar da yanayin juyin halitta zuwa ga tururuwa wanda ya zama girma da girma, daga ƙarshe ya haifar da bacewar nau'in saboda tururuwa ya girma wanda ya hana dabi'ar ciyarwa da kyau kuma ya sa dabbar ta zama tarko a cikin rassan bishiyoyi.  A cikin 1930s, Darwiniyawan da Julian Huxley ya jagoranta sun yi jayayya da orthogenesis, wanda ya lura cewa girman antler bai cika girma ba, kuma ya yi daidai da girman jiki.   Ra'ayin da aka fi so a halin yanzu shine zaɓin jima'i shine ƙarfin motsa jiki a bayan manyan antlers maimakon orthogenesis ko zaɓin yanayi. 

### Juyin Halitta

*M. giganteus* na cikin jinsin *Megaloceros .* An sanya *Megaloceros* sau da yawa a cikin kabilar Megacerini, tare da sauran nau'o'in jinsin da ake kira "barewa mai girma", kamar *Sinomegaceros* da *Praemegaceros* . ** Taxonomy na giant deer ba shi da yarjejeniya, tare da sunayen jinsin da aka yi amfani da su don nau'in nau'i daban-daban tsakanin marubuta.   Rikodi na farko na jinsin shi ne wani yanki na antler daga Early Pleistocene MN 17 (2.5-1.8 Ma) na Stavropol Krai a Arewacin Caucasus na Rasha, wanda aka ba da sunan *M. stavropolensis* a cikin 2016,  duk *da* haka an ba da shawarar wannan nau'in.   ko *Sinomegaceros* .  Mafi tsofaffin rubuce-rubucen da aka yarda da su na jinsin sun fito ne daga farkon Pleistocene marigayi.  Sauran nau'o'in da ake la'akari da su na *Megaloceros* sun hada da reindeer sized *M. savini*, wanda aka sani daga farkon Pleistocene na tsakiya (~ 700,000-450,000 da suka wuce) yankuna a Ingila, Faransa, Spain da Jamus, da kuma kwanan nan da aka kwatanta nau'in *M. novocarthaginiensis*, wanda aka sani daga farkon gida (P.leistocene) a Spain (P.leistocene). ƙananan *M. matritensis* endemic zuwa ga tsibirin Iberian a lokacin marigayi Middle Pleistocene (~ 400,000 zuwa 250,000 shekaru da suka wuce), wanda ya mamaye lokaci-lokaci tare da tarihin *M. giganteus* na farko. Jan van der Made ya ba da shawarar *M. novocarthaginiensis, M. savini* da *M. matritensis* don zama nau'i-nau'i na nau'i-nau'i, saboda halayen halayen halayen halayen da ba a samo su ba a cikin *M. giganteus* da kuma sannu-sannu a hankali canza yanayin halayen halayen ta hanyar lokaci.  *M. savini* da nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i *na Praedama* .  Yayin da ake ba da shawarar zuriyar *M. savini/Praedama* don su kasance da alaƙa *da M. giganteus,* yawancin marubuta sun yarda cewa wannan rukunin na barewa ba zai yiwu ya zama kakannin kakanni na *M. giganteus* ba. 

## Bayani

The Irish elk ya tsaya kusan  tsayi a kafadu,  kuma yana da manyan dabino (lebur da faffadan) tururuwa,  mafi girma a cikin kowane sanannen barewa, tare da mafi girman samfurori sun kai  daga tip zuwa tip  (ko da yake yana da wuya ga samfurori su wuce  a fadin  ) da  a cikin nauyi.  antlers sun fi girma fiye da na moose masu rai, kasancewa a matsakaita fiye da sau biyu na ƙarar tururuwa.  Don girman jiki, a kusan  kuma har zuwa  ko fiye,    dan Irish elk shi ne mafi nauyin da aka sani ("Barewa na Tsohon Duniya");  kuma an ɗaure tare da tsohuwar Alaska moose ( *Alces alces gigas* ) a matsayin na uku mafi girma da aka sani, bayan *Cervalces latifrons* da *Cervalces scotti* .   Siffa da tazara na tururuwa sun bambanta sosai a tsawon lokaci da sararin samaniya, mai yiwuwa yana nuna yadda wasu al'ummomi suka daidaita zuwa wuraren dazuzzuka.  Idan aka kwatanta da *Alces*, ɗan Irish elk yana da alama yana da kwarangwal mai ƙarfi, tare da kwarangwal na *Alces* da suka girma da girma waɗanda ke da kamanni da na firayim ɗin Irish elk, da ƙaramin ɗan Irish elk mai kama da Firayim *Alces* . Wataƙila saboda tsarin zamantakewa daban-daban, ɗan Irish ya nuna alamun dimorphism fiye da *Alces*, tare da kuɗaɗen ɗan Irish suna da girma fiye da yadda yake yi.  Gabaɗaya, tsabar kuɗin Irish na iya kasancewa daga , tare da matsakaicin , kuma yana iya kasancewa yana da girma, kusan 80% na girman buck, ko  a matsakaici.  Haruffa masu bambanta na *M. giganteus* sun haɗa da gabaɗaya gabaɗaya, madaidaiciyar doguwar kwakwalwa, daidaitaccen sashin gaba na gaba na kwanyar (yankin orbitofrontal), tare da rashin manyan canines da molarisation na ƙananan premolar na huɗu (P 4 ). Kwankwan kai da mandila na alƙawarin Irish suna nuna kauri mai girma ( pachyostosis ), tare da farkon kuma cikakke shafewar sutures na cranial . 

Dangane da zane-zanen kogo na Upper Palaeolithic, ɗan Irish elk yana da alama yana da launin haske gaba ɗaya, tare da ɗigon duhu yana gudana tare da baya, ƙwanƙwasa a kowane gefe daga kafada zuwa haunch, wani abin wuya mai duhu a makogwaro da chinstrap, da duhu mai duhu a kan bushes (tsakanin kafada ). A cikin 1989, masanin burbushin halittu Ba'amurke Dale Guthrie ya ba da shawarar cewa, kamar bison, hump ɗin ya ba da damar yin aiki mafi girma na kafafun gaba don ƙara tsayin tafiya yayin gudu. Valerius Geist ya ba da shawarar cewa ana iya amfani da hump ɗin don adana kitse. Rarraba kitse maimakon rarrabawa daidai gwargwado na iya hana zafi fiye da kima yayin da ake gudu ko cikin rugujewa a lokacin bazara. 

## Wurin zama
Ƙwararren ɗan Irish yana da nisa mai nisa, wanda ya tashi daga Tekun Atlantika a Yamma zuwa tafkin Baikal a Gabas. Irish elk ba su bayyana sun mika zuwa arewa uwa da bude mammoth steppe a Siberiya, maimakon kiyaye ga boreal steppe- woodland muhallin, wanda kunshi warwatse spruce da Pine, kazalika da low-kwance ganye da shrubs ciki har da ciyawa, sedges, *Ephedra, Artemisia* da Chenopodiaceae .  Dabbobin sun bayyana suna da digiri na filastik na muhalli, kamar yadda a lokacin tsaka-tsakin tsaka-tsakin lokaci kafin Holocene, nau'in ya kasance a cikin yanayin gandun daji na Turai.   A cikin waɗannan lokutan, nau'in galibi suna da ƙarancin tururuwa fiye da lokacin lokacin dusar ƙanƙara, mai yiwuwa a matsayin daidaitawa don motsawa ta cikin wuraren dazuzzuka. 

## Manazarta