Damisa ta teku Wata halitta ce mai ban mamaki wacce take rayuwa a cikin ruwan Antarctic. Kodayake waɗannan hatiman suna taka rawa ta musamman a cikin yanayin halittar Antarctic, galibi ana rashin fahimtarsu a matsayin jinsin. Akwai fannoni da yawa masu ban sha'awa game da rayuwar wannan babban mai cutar Kudancin Kudancin wanda ya kamata ya sani. Irin wannan hatimin kusan a saman jerin abincin yake. Ya sami sunanta ne saboda yanayin launinsa.
Asalin jinsin da bayanin
Hoto: Dambar damisa
Tun da daɗewa an ɗauka cewa dabbobi masu shayarwa na rukuni sun samo asali ne daga kakanin kakanni da ke rayuwa a ƙasa, amma har yanzu ba a sami tabbataccen shaidar wannan ba. Gano burbushin halittu Puijila darwini, wanda ya rayu a Arctic a lokacin Miocene (shekaru miliyan 23-5 da suka wuce), ya zama wannan mahaɗan ɓacewa. An samo kwarangwal mai kyau a tsibirin Devon na Kanada.
Daga kai zuwa wutsiya, ya auna santimita 110 kuma yana da ƙafafun ƙafafu a maimakon fincin da zuriyarsa na zamani ke fitowa. Feetafafun kafafun yanar gizo za su ba shi damar yin wani ɗan lokacin farautar abinci a cikin tabkuna na ruwa, yana mai sa tafiya a ƙasa ba ta da matsala kamar ta flippers a lokacin hunturu, lokacin da tabkuna masu daskarewa za su tilasta shi ya nemi abinci a kan ƙasa mai ƙarfi. Doguwar jela da gajerun kafafu sun ba shi kamannin kogin otter.
Bidiyo: Alamar damisa
Kodayake ana zaton cewa asalin dabbobi asalinsu sun samo asali ne daga rayuwar halittun ruwa, wasu - kamar kakannin whales, manatees da walruses - daga karshe sun sake komawa cikin muhallin halittun ruwa, suna mai da wadannan jinsunan rikon kwarya kamar Puijila wata muhimmiyar sarka a tsarin juyin halitta.
Masanin kimiyyar dabbobi na Faransa Henri Marie Ducroty de Blainville shine farkon wanda ya bayyana tambarin damisa (Hydrurga leptonyx) a cikin 1820. Jinsi ne kawai a cikin jinsin Hydrurga. Dangin ta mafi kusanci sune Ross, crabeater da hatimin Weddell, wanda aka fi sani da tambarin Lobodontini. Sunan Hydrurga na nufin "ma'aikacin ruwa" kuma leptonyx Girkanci ne don "ɗan ƙaramin fata".
Bayyanar abubuwa da fasali
Hoto: Damisar dabba
Idan aka kwatanta da sauran hatimai, tambarin damisa yana da cikakkiyar siffar jikin mutum. An san wannan nau'in ne saboda girman kai da muƙamuƙan kama, wanda ya sa ya zama ɗaya daga cikin manyan masu farauta a cikin muhalli. Babban fasalin da ke da wuya a rasa shi ne gashi mai kariya, tare da gefen dokin gefen rigar yana da duhu fiye da ciki.
Hannun damisa suna da azurfa zuwa gashi mai launin toka mai launin toka mai launin shuɗi wanda ya dace da zane mai launi, yayin da gefen ƙyallen (ƙarƙashin) suturar ya fi launi launi, daga fari zuwa launin toka mai toka. Mata sun fi maza girma. Jimlar tsawon ta kasance 2.4-3.5 m, kuma nauyin daga 200 zuwa 600 kg. Sun yi kusan tsawon daidai da na walrus na arewa, amma nauyin hatiman damisa ya kusan rabi ƙasa.
Arshen bakin hatimin damisa koyaushe yana lanƙwasa sama, yana haifar da ruɗar murmushi ko murmushin hadari. Waɗannan fuskoki na fuska ba da son rai ba suna ƙara wa dabbar tsoro da ba za a amince da ita ba. Waɗannan su ne masu saurin cin zafin nama waɗanda ke lura da abin da suke ganuwa koyaushe. A wasu lokuta ba safai ba, lokacin da zasu fita zuwa tudu, suna kiyaye sararin samaniyarsu, suna fitar da hayaniyar gargadi ga duk wanda ya kusa.
Sealaƙƙarfan rufin damisar damisa yana ba shi damar samun saurin gudu a cikin ruwa, yana yin aiki tare tare da ƙafafun gabanta masu tsayi sosai. Wani sanannen halayyar ita ce gajere, gashin-baki, wanda ake amfani dashi don nazarin yanayin. Hannun damisa suna da babbar baki dangane da girman jiki.
Hakoran gaba suna da kaifi, kamar na sauran dabbobi masu cin nama, amma molar suna da alaƙa da juna ta yadda za a tsinka krill ɗin daga cikin ruwa, kamar hatimin crabeater. Ba su da auricles na waje ko kunnuwa, amma suna da magudanar kunne na ciki wanda ke haifar da buɗewar waje. Jin a cikin sararin samaniya daidai yake da ji a cikin mutane, kuma hatimin damisa yana amfani da kunnuwansa, tare da gashin bakinsa, don bin sawun abincin da ke cikin ruwan.
Ina ruwan damisa yake rayuwa?
Photo: Antarctica Damisa Seal
Waɗannan sune hatimin pagophilous, zagayen rayuwa wanda yake da alaƙa da murfin kankara. Babban mazaunin tekun Antarctic yana tare da kewayen kankara. Ana lura da yara a bakin tsibirin subantar. Hakanan an hango wasu bakunan dabbobin da suka ɓace a bakin tekun Ostireliya, New Zealand, Kudancin Amurka da Afirka ta Kudu. A watan Agusta 2018, an ga mutum guda a Geraldton a gabar yammacin Australia. Yammacin Antarctica yana da mafi yawan yawan tambura na damisa fiye da sauran yankuna.
Gaskiya mai Nishaɗi: Damisar da keɓaɓɓu na kadawa a kan wasu dabbobi masu shayarwa da penguins a cikin ruwan Antarctic mai kankara. Kuma lokacin da basu shagala da neman abinci ba, suna iya yawo a kan kankara su huta. Kwalliyar su ta waje da murmushin da ba za a iya kuskurewa ba yasa su cikin sauƙin ganewa!
Yawancin membobin jinsin sun kasance a cikin kangon fakitin a duk shekara, suna keɓewa gaba ɗaya ga mafi yawan rayuwarsu, ban da lokacin da suke tare da mahaifiyarsu. Wadannan rukuni na mahaifa na iya yin tafiya zuwa arewa a lokacin hunturu na Australiya zuwa tsibiran da ke gabar teku da kuma gabar tekun nahiyoyin kudu don tabbatar da kula da 'ya'yan maruran. Yayinda wasu keɓaɓɓun mutane na iya bayyana a ƙananan yankunan latitude, mata ba sa yin haihuwa a can. Wasu masu bincike sunyi imanin cewa wannan ya faru ne saboda damuwa da lafiyar 'ya'ya.
Me tambarin damisa yake ci?
Hoto: Dambar damisa
Hannun damisa shine babban mai farauta a yankin polar. Ci gaba da saurin har zuwa 40 km / h da ruwa zuwa zurfin kusan 300 m, yana barin ganimarta da ɗan damar tsira. Hannun damisa suna da nau'ikan abinci iri-iri. Antarctic krill sune kusan 45% na jimlar abinci. Abincin zai iya bambanta dangane da wuri da kuma samfuran samfuran abubuwa masu daɗi. Ba kamar sauran dangi ba, abincin hatiman damisa kuma ya hada da dabbobi masu shayar da ruwa na Antarctic.
Mafi yawanci sukan fada cikin ganimar yunwar da damisa ta damisa:
- hatimin crabeater;
- Antarctic furfin hatimi;
- kunnen kunne;
- penguins;
- Hatimin Weddell;
- kifi;
- tsuntsaye;
- cephalopods.
Kamanceceniya tare da sunan mai suna sun fi canza launi kawai. Hannun damisa sune mafi girman mafarautan dukkanin hatimi kuma sune kawai waɗanda ke cin abincin ganima mai dumi. Suna amfani da haƙoransu masu ƙarfi da dogayen haƙoransu don kashe ganima. Arewararrun mafarauta ne waɗanda yawanci suke jira a ƙarƙashin ruwa kusa da kankara kuma su kama tsuntsaye. Hakanan zasu iya tashi daga cikin zurfin kuma kama tsuntsaye a saman ruwa a cikin muƙamuƙansu. Shellfish ba sa zama ganima sosai, amma muhimmin ɓangare na abincin.
Gaskiyar wasa: Lambar damisa ita ce sananniyar hatimi don farautar farautar jini mai dumi a kai a kai.
Wani abin al'ajabi ya faru tare da mai ɗaukar hoto Paul Nicklen, wanda, duk da haɗarin, shi ne farkon wanda ya fara nitsewa cikin ruwan Antarctic don kama tambarin damisa a muhallinsu. Maimakon sharrin aljan, ya gamu da wata kyakkyawar mace mai damisa, wacce wataƙila ta ɗauka cewa tana gaban hatimin jariri ne da ba shi da hankali.
Kwanaki da yawa, ta kawo penguins masu rai da matattu azaman abinci ga Nicklen kuma tayi ƙoƙarin ciyar dashi, ko kuma aƙalla koya masa farauta da ciyar da kansa. Don tsananin firgita, Nicklen ba ta cika sha'awar abin da za ta bayar ba. Amma ya sami hotuna masu ban mamaki na mai farauta mai ban sha'awa.
Fasali na ɗabi'a da salon rayuwa
Hoto: Dambar damisa
Karatun ya nuna cewa a matsakaita, iyakar nutsewar aerobic ga matasa hatimi yakai minti 7. Wannan yana nufin cewa a lokacin watannin hunturu, tambarin damisa ba ya cin krill, wanda shine babban ɓangare na abincin tsofaffin hatimi kamar yadda ake samun krill da zurfi. Wannan wani lokaci yakan haifar da farauta tare.
Gaskiya mai ban sha'awa: Akwai lokuta na neman farauta tare da hatimin zinare na Antarctic, wanda aka sanya ta hatimin matasa kuma wataƙila mahaifiyarsa tana taimaka wa ɗanta girma, ko wataƙila mace + maza biyu don ƙara yawan farautar farauta.
Lokacin da damisar damisa suka gundura da cin abinci amma har yanzu suna son yin nishaɗi, suna iya yin kuli da linzami tare da penguins ko wasu like. Lokacin da penguin ya fara iyo zuwa bakin teku, tambarin damisa yakan yanke hanyar tserewarsa. Yana yin hakan akai-akai har sai penguin ɗin ya sami damar isa gaɓar, ko kuma ya shanye saboda gajiya. Da alama babu ma'ana a cikin wannan wasan, musamman tunda hatimin yana cinye ƙarfi mai yawa a cikin wannan wasan kuma mai yiwuwa ma ba sa cin dabbobin da suka kashe. Masana kimiyya sun yi hasashen cewa wannan a fili yake ga wasanni, ko kuma zai iya zama matasa, hatimin da ba su balaga ba suna neman su ƙware da dabarun farautar su.
Hannun damisa suna da ma'amala mara kyau da juna. Gabaɗaya suna yin farauta su ɗaya kuma basu taɓa haɗuwa da wasu mutane fiye da ɗaya ko biyu na jinsinsu a lokaci guda. Banda wannan ɗabi'ar kadaitaka ita ce lokacin kiwo na shekara-shekara daga Nuwamba zuwa Maris, lokacin da mutane da yawa za su yi aure tare. Koyaya, saboda ɗabi'unsu na rashin daɗi da yanayin kadaici, ba a san komai game da cikakken yanayin haihuwar su. Masana kimiyya har yanzu suna kokarin gano yadda tambarin damisa ke zabar abokan aurensu da kuma yadda suke tantance yankunansu.
Tsarin zamantakewa da haifuwa
Photo: Seulla damisa
Saboda hatimun damisa suna zaune a yankunan da ke da wahalar isa, ba a san komai game da halayen kiwo ba. Koyaya, tsarin kiwonsu an san cewa yana da aure fiye da daya, ma'ana, maza suna saduwa da mata da yawa yayin saduwarsu. Mace mai sha’awar jima’i (shekaru 3-7) zata iya haifar ɗan maraƙi a lokacin bazara ta hanyar haɗuwa da namiji mai lalata (shekaru 6-7).
Mating yana faruwa ne daga Disamba zuwa Janairu, jim kaɗan bayan yaye yayan da suka girma, lokacin da mace take da oestrus. A shirye-shiryen haihuwar hatimin, matan na haka rami zagaye a cikin kankara. Jaririn da aka haifa ya kai kimanin kilogiram 30 kuma yana tare da mahaifiyarsa tsawon wata ɗaya kafin a yaye shi kuma a koya masa farauta. Hatimin namiji baya shiga cikin kula da matasa kuma ya dawo cikin salonsa na kadaici bayan lokacin saduwa. Yawancin kiwo na hatiman damisa na faruwa ne a kan kangon fakiti.
Gaskiya mai ban sha'awa: Saduwa tana faruwa a cikin ruwa, sannan namiji ya bar mace don kula da dan, wanda ta haifa bayan kwanaki 274 na ciki.
An yi imanin cewa sautin sauti yana da matukar mahimmanci yayin kiwo, saboda maza sun fi aiki sosai a wannan lokacin. An yi rikodin waɗannan kalmomin kuma ana nazarin su. Kodayake ba a san komai game da dalilin da ya sa maza ke fitar da waɗannan sautuka ba, ana tsammanin suna da alaƙa da ɓangarorin haɓakawa da halayyar haihuwa. Dakatar da juyi da jujjuyawa daga gefe zuwa gefe, mazan da suka manyanta suna da halaye, salon da aka tsara wanda suke haifuwa da tsari na musamman kuma wadanda aka yi amannar suna daga cikin halayen kiworsu.
Daga 1985 zuwa 1999, an yi tafiye-tafiyen bincike guda biyar zuwa Antarctica don nazarin hatimin damisa. An lura da kusurwa daga farkon Nuwamba zuwa ƙarshen Disamba. Masana kimiyya sun lura cewa akwai kusan maraki daya ga kowane baligi uku, kuma sun ga cewa yawancin mata sun nisanci sauran manyan hatiman a wannan lokacin, kuma idan aka gan su a cikin rukuni, ba su nuna alamar ma'amala ba. Yawan mace-macen damisa a shekarar farko ta kusan zuwa 25%.
Abokan gaba na dabbobin damisa
Hoto: Dambar Damisa a Antarctica
Dogaro da tsarin rayuwa mai kyau ba sauki a Antarctica, kuma hatiman damisa suna da sa'ar samun kyakkyawan abinci kuma kusan babu masu farauta. Kifi Whale ne kawai ƙaddarar mahaɗan waɗannan hatimin. Idan waɗannan like ɗin suka sami damar tserewa daga fushin whale mai kashe, za su iya rayuwa har zuwa shekaru 26. Kodayake hatimun damisa ba sune mafi girman dabbobi masu shayarwa a duniya ba, zasu iya rayuwa na tsawon lokaci mai ban sha'awa saboda yanayin mawuyacin hali da kuma karko. Baya ga kifin whale, ƙananan tambura na damisa kuma ana iya farautar su ta manyan kifaye da maƙalarin giwayen. Canines na dabba sune 2.5 cm.
Oƙarin nazarin waɗannan halittu na iya zama haɗari, kuma a wani yanayi, sananne ne tabbatacce cewa hatimin damisa ya kashe mutum. Ba da dadewa ba, wani masanin kimiyyar halittar ruwa da ke aiki a cibiyar binciken Antarctic ta Burtaniya ya nitse bayan da wani hatimi ya ja shi kusa da mita 61 a kasa da matakin ruwa. A halin yanzu ba a san ko tambarin damisa na nufin ya kashe masanin halitta ba, amma mafi mahimmanci, tunatarwa ce ta haƙiƙanin halayen waɗannan dabbobin daji.
Lokacin farautar penguins, tambarin damisa yana sintiri a gefen ruwan kankara, kusan ya nitse cikin ruwan, yana jiran tsuntsayen su nufi cikin teku. Yana kashe penguins masu ninkaya ta hanyar kamo ƙafafunsu, sannan kuma yana rawar jiki da tsuntsu kuma yana ta bugun jikinsa akai akai har zuwa lokacin da penguin ya mutu. Rahotannin da suka gabata na hatiman damisa da ke tsabtace kayan abincinsu kafin ciyarwa an gano ba daidai bane.
Rashin haƙoran da suka zama dole a yanyanka ganimarta gunduwa-gunduwa, tana jujjuya abincinta daga gefe zuwa gefe, yana tsaga shi ƙananan ƙananan. A lokaci guda, ana cin krill ta hanyar tsotsa ta haƙoran hatimin, wanda ke ba da damar damun damisa ya sauya zuwa hanyoyin ciyarwa daban-daban. Wannan daidaitawa na musamman na iya nuna nasarar hatimi a cikin yanayin halittar Antarctic.
Yawan jama'a da matsayin jinsin
Hoto: Dambar damisa
Bayan hatimin Crabeater da Weddell, damisar damisa ita ce mafi hatimin hatta a Antarctica. An kiyasta yawan mutanen wannan nau'in daga 220,000 zuwa 440,000, wanda ke sanya tambarin damisa "na Lean Damuwa". Duk da yawan tambarin damisa a Antarctica, suna da wahalar yin karatu tare da hanyoyin gani na gargajiya saboda suna yin dogon lokaci a karkashin ruwa a lokacin bazara na Australiya da lokacin bazara lokacin da ake gudanar da binciken gani a al'adance.
Hannunsu na musamman na ƙirƙirar sauti a cikin ruwa don tsawan lokaci ya ba da damar ƙirƙirar hotunan hoto, wanda ya taimaka wa masu bincike fahimtar yawancin halayen wannan dabba. Hannun damisa suna cikin tsari mafi girma kuma suna da haɗari ga mutane. Koyaya, hare-hare kan mutane ba safai ba ne. Misalan halayen tashin hankali, tursasawa da kai hare-hare an yi rubuce-rubuce. Abubuwan da suka faru sun hada da:
Thomas Ord-Fox, memba ne na Tattakin-Antarctic Expedition na shekara ta 1914-1917, yayin da balaguron ke kan tekun kankara. Alamar damisa, mai tsawon kusan mita 3.7 kuma nauyinta yakai 500, ta bi Ord Lee akan kankara. An cece shi ne kawai lokacin da wani memba na balaguron, Frank Wilde, ya harbe dabbar.
A cikin 1985, ɗan Scotland ɗan binciken Gareth Wood ya ciji sau biyu a ƙafa lokacin da hatimin damisa ya yi ƙoƙarin jan shi daga kankara zuwa cikin teku. Abokansa sun sami nasarar kubutar da shi ta hanyar kaɗa shi a kai a cikin takalmi mai tsini. Mutuwa kawai da aka rubuta ya faru ne a 2003, lokacin da hatimin damisa ya far wa masanin kimiyyar halittar ruwa Kirsty Brown ya jawo shi cikin ruwa.
Bayan haka tambarin damisa nuna halin kai farmaki ga baki pontoons daga kwale-kwalen masu iya kumbura, bayan hakan ya zama dole a tanadar musu da wasu na'urorin kariya na musamman don hana hudawa.
Ranar bugawa: 24.04.2019
Ranar sabuntawa: 19.09.2019 a 22:35
