Ukucinga ngesilwanyana esaqala ukudada kwinkulungwane ye-17 kwaye sisaphila nanamhlanje kusenokuvakala ngathi kukugqithisela, kodwa idatha ikhomba kanye kuloo nto: Ushaka waseGreenland Ehlalutywa zizazinzulu zamazwe ngamazwe, wayeza kuzalwa malunga nowe-1627 kwaye wayeza kuba kufutshane 399 iminyakaOku kufunyaniswa kwakhe kumbeka njengo isilo esinethambo lomqolo esiphile ixesha elide esaziwayo ukuza kuthi ga ngoku, ngaphezulu kakhulu kweemfudo ezinkulu, iiminenga okanye iintlanzi eziphile ixesha elide.
Ityala lale shark yaseArctic aliyondaba ingaqhelekanga, kodwa liphambili kuluhlu lophando oluye lwaguqula ukuqonda kwethu ukwaluphala kangangeminyaka. Ngenxa yokudibanisa izifundo zentsimi kwi Ulwandlekazi lweArctic kunye neNorth Atlantic Ngeendlela ze-molecular ezisemgangathweni ophezulu, abaphandi baqala ukufumanisa indlela isilwanyana esinokugcina ngayo umzimba waso—kwaye nokubona kwaso—kusebenza kangangeenkulungwane ezininzi.
Uphando olufumanise ishark eneminyaka ephantse ibe yi-400 ubudala
Ibali lale shark eneminyaka engama-399 ubudala laqala ukuthandwa ngo-2016, xa iphepha lapapashwa kwijenali edumileyo. inzululwazi beka uhlobo ISomniosus microcephalus embindini wengxoxo yesayensi. Iqela lamazwe ngamazwe lahlalutya Iintlanzi zaseGreenland ezingama-28 ezibanjwe ngengozi ngabalobi kumanzi abandayo asemantla, ngenjongo yokuqikelela ubudala bayo bokwenyani, into eyayiphantse ibe yimfihlakalo ukuza kuthi ga ngelo xesha.
Endaweni yokusebenzisa indlela yakudala yokuloba iishark—ukubala izangqa zokukhula kwithambo lomqolo—abaphandi bakhethe indlela ephucukileyo ngakumbi: Umhla we-radiocarbon weelensi zamehloLe tissue yamehlo isebenza njengohlobo lwe-archive yebhayoloji, kuba yakhiwa kwasekuqaleni kobomi besilwanyana kwaye Ayize ivuselelekeukuze igcine "uphawu" lwekhemikhali lwexesha eyazalwa ngalo.
Ukuthelekisa loo signal ye-radiocarbon kunye iirekhodi zembali ze-carbon-14Kuquka ukunyuka okwaveliswa luvavanyo lwenyukliya ngeminyaka yoo-50 noo-60, iqela lakwazi ukuphucula kakhulu uqikelelo lweminyaka. Isiphumo sagqiba kwelokuba: Ubudala obuqhelekileyo bezinto ezisetyenzisiweyo yayingama-272 eminyaka ubuncinane., kwaye eyona inkulu, ingaphezulu kweemitha ezintlanu ubude, yayijikeleze i Iminyaka eli-399 yobomi, ukuzalwa kwakhe kuqikelelwa ekuqaleni kwenkulungwane ye-17.
Le rekhodi ipheleleyo yokuphila ixesha elide kwizilwanyana ezinethambo lomqolo yenza iGreenland shark ibe "yifosili ephilayo" yokwenyani kwisayensi. Abaphandi abafana neDenmark UJulius NielsenOmnye wababhali bolu phononongo ugxininise ukuba luhlobo oluthile ukukhula okucothayo kakhulu kunye nobukhulu obukhulueyayisele ikhombe kulindelo lobomi oluphezulu kakhulu kunolo lwezinye izilwanyana ezifanayo.
I-metabolism ecothayo: ukukhula kwesentimitha enye ngonyaka
Imfihlo enkulu yale shark ikwixesha layo lobomi. Nangona iintlobo ezininzi zaselwandle zikhula ngokukhawuleza kwaye zizala kwangethuba, ishark yaseGreenland isebenza ngesantya esahlukileyo. Ayinawo ubude obumalunga nesentimitha enye ngonyakaOku kuthetha ukuba zizilwanyana ezinokufikelela phakathi kweemitha ezintlanu nezisixhenxe ukuphakama emva kweenkulungwane zokukhula okuqhubekayo.
Oku kucotha kubonakala nakwindlela ezizala ngayo: uphando lubonisa ukuba Ayifikeleli ekuvuthweni ngokwesondo ide ibe malunga neminyaka eyi-150 ubudala.Enyanisweni, oku kuthetha ukuba imazi ingahamba inkulungwane enesiqingatha ngaphambi kokuba izale okokuqala. Lo mjikelo wobomi ocothayo kakhulu unceda ukuchaza ubude bayo, kodwa kwangaxeshanye yenza ukuba inani lazo... ngakumbi ukuba sengozini yokuloba ngokugqithisileyo naluphi na ukwanda kokufa.
Imeko-bume yendalo ehlala kuyo nayo ibalulekile. Le shark ihlala kwi- amanzi abandayo, anzulu eArctic naseMantla eAtlantikirhoqo kubunzulu obungaphezulu kweemitha ezingama-2.000, apho ubushushu buhlala busondele kwingqele kwaye iimeko zizinzile kakhulu. Kule meko imbi kakhulu, isilwanyana siye saphuhla imetabolism ephantsi kakhuluokukuvumela ukuba wonge amandla kwaye unciphise ukuguguleka kweeseli ixesha elide.
Iingcali eziphanda ngookrebe nezinye izilwanyana ezinkulu zaselwandle ezinethambo lomqolo zithi ubushushu nobunzulu asikokuphela kwezinto ezichaza ukuqina kwazo. Kukho ubungqina obuqinileyo bokuba olu hlobo lunayo iindlela zeseli ezisebenzayo kakhulu zokulungisa i-DNA, into ethathwa njengeyona nto iphambili ekulweni nokwaluphala kunye nophuhliso lwezifo eziwohlokayo.
Isigebenga esingathethiyo seArctic: ubungakanani, ukutya kunye nokuziphatha
Ngaphaya kobudala bayo, iGreenland shark sisilwanyana esihlonitshwayo ngenxa yobukhulu bayo. Iirekhodi zithetha ngemizekelo yokuba Zinokufikelela kwiimitha ezisixhenxe ubude kwaye zinobunzima obungaphezu kwetoni.Imifanekiso ifana neyee-great white sharks, kodwa ineendlela zokuziphatha ezahluke kakhulu.
Nangona inkulu, idada kancinci ngendlela emangalisayo. Ubungakanani bubonisa ukuba Ayifane idlule iikhilomitha ezimbini ngeyure.Oku kwenza ukuba, emehlweni abantu, ibe "yingxilimbela ecothayo" ehamba ngokuzolileyo elwandle. Oku kucotha kuhambelana nokuncipha kwemetabolism yayo kunye nesidingo sayo sokuba ukuphucula inkcitho yamandla kangangoko kunokwenzeka kwindawo apho ukutya kungasoloko kuninzi.
Ngokuphathelele ukutya, kukutya okubanzi. Kubonakalisiwe ukuba kudla intlanzi, i-squid, izinja zamanzi kwaneentsalela zezinye izilwanyana ezitshona ezantsi. Olu buchule bokuhlutha buyivumela ukuba iphile kwiindawo apho ukufumaneka kwezilwanyana eziphilayo kunokungalingani khona. ukuveliswa kwe-ovoviviparous, kunye nenzala ekhula kumaqanda ngaphakathi emzimbeni kamama, igqibezela uluhlu olungaqhelekanga lwezinto eziphilayo.
Iprofayili yale shark njenge "sigebenga esithuleyo" saseArctic ibangele ukuthelekiswa okuninzi nezinye iintlobo eziphila ixesha elide, kodwa akukho nanye ebonakala ngathi isondela kubomi bayo. Nangona ezinye iifudo okanye imikhomo zinokuphila ixesha elingaphezu kwekhulu leminyaka, iinkulungwane ezintathu okanye ezine zobomi obunokwenzeka Ushaka waseGreenland ubekwe kwindawo yawo ngaphakathi kobukumkani bezilwanyana.
I-retina engagugiyo: indlela esibona ngayo isilwanyana esineminyaka ephantse ibe ngamakhulu amane eminyaka
Kwiminyaka yakutshanje, uphando ngale shark luye lwanda kakhulu ngokugxila kwisitho esithile: iliso. Phakathi kowama-2020 nowama-2024, iqela leengcali zenzululwazi zamazwe ngamazwe ezazisebenza kwindawo yeSiqithi saseDisko, kufutshane neGreenlandWasebenzisa amathuba amatsha okuthatha iisampulu ukuze afunde ngokweenkcukacha ulwakhiwo kunye nomsebenzi we-retina kwiisampulu ezindala kakhulu.
Ukudibanisa iindlela zokusebenzisa i-genomics, i-transcriptomics kunye ne-histologyAbaphandi bakwazile ukuchaza ngokuchanekileyo indlela izicubu zamehlo ezicwangciswe kwaye zigcinwa ngayo kwezi zilwanyana. Enye yezona zinto zibalulekileyo ezifunyenweyo yayikukuba ukwakheka okungaqhelekanga kweekhemikhali kwiimembrane zeseli ze-retina, ityebile kwii-lipids ezikhethekileyo kakhulu.
Xa kuthelekiswa i-retina yeshark yaseGreenland neyezilwanyana ezanyisayo ezahlukeneyo zasemhlabeni, ingakumbi inani eliphezulu le- ii-fatty acids ezinde kakhulu (ii-VLC-PUFA) kunye ne-DHAOlu didi lusebenza njenge "oyile esemgangathweni ophezulu" Ayiqini okanye ilahlekelwe bukuguquguquka xa amaqondo obushushu esondele ekuqandeni.ivumela i-rhodopsin—iproteni ebamba ukukhanya—ukuba iqhubeke isebenza ebumnyameni bobunzulu obukhulu.
Abaphandi abafana no UDorota Skowronska-KrawczykAbaphandi abavela kwiYunivesithi yaseCalifornia, e-Irvine, bagxininise ukuba le retina, iyakwazi ukugcina esebenzayo kwaye “iselula” kangangeenkulungwane Oku kuvula iindlela ezinomdla kakhulu zokuqonda nokunyanga izifo zamehlo zabantu ezinxulumene nokwaluphala, ezifana nokubola kwe-macular okanye i-glaucoma. Ingcamango yokuba izicubu ezithambileyo ezinjalo zinokunyamezela amakhulu eminyaka ngaphandle kokubonisa iimpawu zokuwohloka okukhulu inomtsalane kakhulu kumayeza.
I-genome enkulu kunye ne-DNA ezilungisa rhoqo
Umdla wesayensi kwesi silwanyana awupheleli nje emehlweni aso. Izifundo zakutshanje zebhayoloji yeemolekyuli zivumele ukulandelelanisa ngokupheleleyo i-genome yeshark yaseGreenlandityhila ikhowudi yemfuza enobukhulu obungaqhelekanga: kuqikelelwa ukuba iqulethe malunga I-6.500 yezigidi zezibini ezisisiseko, malunga nobukhulu obuphindwe kabini kunobomntu kwaye yenye yezona zinkulu ezichazwe kooshaka.
Inxalenye enkulu yelo genome yenziwe izinto eziguquguqukayo, oko kubizwa ngokuba “zii-jumping genes”Ezi ntlobo zithathwa njengengxaki kuba zinokuphazamisa i-DNA. Nangona kunjalo, kule meko, kurhanelwa ukuba zinegalelo ekuphindaphindweni nasekuqinisweni kwayo. iijini ezinxulunyaniswa nokulungiswa kwezakhi zofuzoinkqubo ebalulekileyo yokugcina ukuthembeka kweeseli kangangeenkulungwane.
Kule nkqubo-sikhokelo, ii-genes ezifana nezi zilandelayo ziyabonakala: i-ercc1 kunye ne-ercc4ebandakanyeka ekulungiseni umonakalo we-DNA, kunye nokuguqulwa kweproteni ethile TP53, eyaziwa ngokuba “ngumlindi we-genome.” Kwezinye iintlobo, ezi molekyuli zinceda ekuthinteleni uphuhliso lweethumba kunye nokuwohloka kweeseli kancinci; kwishark yaseGreenland, ukubonakaliswa okuphezulu nokuqhubekayo Kubonakala ngathi isebenza njengenkqubo yokugcina izicubu ngokusisigxina.
Olu luhlu lohlengahlengiso lwezakhi zofuzo kunye ne-biochemical luye lwakhokelela kumaqela amaninzi ophando aseYurophu naseMntla Melika, kuquka lawo KwiYunivesithi yaseCopenhagen kunye neYunivesithi yaseCalifornia, ukuba baqwalasele le shark njenge imodeli yokuziphendukela kwemvelo yokuxhathisa ukwaluphalaUkuqonda ngokweenkcukacha indlela esebenza ngayo le "phakheji" yeendlela zokukhusela kunokuba nemiphumo ethe ngqo kwiinkalo ezifana ne-geriatrics, i-oncology, okanye i-ophthalmology.
Okwangoku, ubungqina babo basebenza ngqo neesampuli bubonisa indlela ezibalaseleyo ngayo ezi sampuli. UEmily Tom, naye ovela kwiYunivesithi yaseCalifornia, ubalise indlela, xa evula enye yeempahla ezithunyelweyo, wafumana "ibhola yeliso eneminyaka engama-200 ubudala" iphelele eqhweni elomileyo kwaye ngaphandle kweempawu ezicacileyo zokufa okukhulu kweeseliUmzekelo ocacileyo wendlela la malungu aphikisana ngayo nolindelo oluqhelekileyo ngokuhamba kwexesha.
Imodeli yendalo yokufunda ubomi obude… kulwandle olusengozini
Lonke olu lwazi lubeka ishark yaseGreenland kwindawo ekhethekileyo: ngoko nangoko, yi- uphawu lokuphila ixesha elide kakhulu kunye neentlobo ezisengoziniIsantya sokukhula kwazo kancinci, ukuvuthwa kwazo ngasemva, kunye nendawo yazo yokuhlala ekhethekileyo kuthetha ukuba nayiphi na impembelelo yomntu inefuthe elihlala ixesha elide kubemi bazo.
Phakathi kwezona ngcinezelo ziphambili kukho ukubambisa —xa ibanjwa kwizixhobo ezenzelwe ezinye iintlobo zezilwanyana—, ungcoliseko olufikelela kwiArctic kunye notshintsho oluhambelana ukufudumala kwehlabathiOlu tshintsho lutshintsha ubushushu, imisinga, kunye nokufumaneka kokutya emanzini apho kuhlala khona. Nangona ukubalwa kwabantu okuchanekileyo kungekafumaneki okwangoku, iingcali ziyavuma ukuba ukulondolozwa kwale shark kufuna indlela yexesha elide.
EYurophu, amaziko afana ne- IYunivesithi yaseCopenhagen kunye namaziko ophando eArctic Bagxininisa kwimfuneko yokugcina uxinzelelo lokuloba luphantsi kolawulo kwiindawo apho olu hlobo luvela khona kunye nokuqinisa iinkqubo zokubeka esweni zesayensi. Isizathu asikokugcina isilwanyana esihlaselayo kuphela, kodwa sikwakho ukukhusela inqaku eliphambili lokuqonda ukuguquka kobomi kwiimeko ezimandundu.
Njengoko kusenziwa inkqubela phambili ekuchazeni iindlela zayo zofuzo, iiseli, kunye nokusebenza komzimba, ishark yaseGreenland iya isiba yi- ilebhu yokuphila ixesha elide yendaloUlwazi ngalunye olutsha malunga nendlela egcina ngayo i-retina yayo isebenza, indlela elungisa ngayo i-DNA yayo, okanye indlela elawula ngayo imetabolism yayo emanzini aphantse abe ngumkhenkce lunika iingcebiso eziluncedo zokujongana neengxaki zempilo zabantu ezinxulumene nokwaluphala.
Ukuba isilwanyana esinomqolo elwandle sinokuphila iinkulungwane ezintathu ukuya kwezine, sisinde kwiimfazwe, kwiinguqu kwezoshishino, nakutshintsho lwemozulu ngelixa sidada buthule phantsi komkhenkce, kusinyanzela ukuba sicinge kwakhona ngemida esiyibeka kubomi. Ushaka waseGreenland, ingakumbi lowo mzekelo uqikelelwa ukuba 399 iminyakaNgoko ke iye yaba sisikhumbuzo sendlela indalo enokuba mangalisa ngayo xa ijongwa ngokusondeleyo nangokunzulu.
