Oshaka bebezulazula olwandle amakhulu ezigidi zeminyaka, kodwa siyaqhubeka nokuthola izinto ezintsha ngabo njalo eminyakeni embalwa. Lezi zilwane ezinkulu zasolwandle azizona nje izinkanyezi zama-movie asabekayo: ziyisihluthulelo sokulinganisela kolwandle nolwandle, futhi i-biology yazo ihlukile kangangokuthi ichitha imibono eminingi esinayo.
Kunokuba nje “imishini yokubulala,” oshaka banengqondo ethuthuke kakhulu, izinzwa ezibukhali, namasu okuzala ayinkimbinkimbi . Kuyo yonke le ndatshana, sizohlola ngokuthula kodwa ngokucophelela ukwakheka kwabo, ukuvela kwemvelo, izinzwa, ukuziphatha, ukudla, ukuzala, ubudlelwano nabantu, kanye nesimo sokulondolozwa, sihlanganisa okwaziwayo ngoshaka basolwandle ngokujwayelekile kanye nezinhlobo zabo eziningi ezidumile.
Iyini ngempela ushaka? I-Taxonomy kanye nokuziphendukela kwemvelo
Uma sikhuluma ngoshaka, sibhekisela kuSelachii , iqembu elingaphakathi kwezinhlanzi ezinamafutha . Ziyingxenye ye-Elasmobranchii, ehlanganisa nemisebe kanye nemisebe ye-manta; zonke, kanye nama-chimera, zakha iqembu elikhulu lamaChondrichthyes.
Oshaka babonakala ngohlaka lwabo lwe-cartilaginous, izimbobo ezinhlanu kuya kweziyisikhombisa ze-gill ohlangothini ngalunye lwekhanda , izikali ze-placoid (ama-dermal denticles), kanye nama-free pectoral fins, okusho ukuthi awahlanganiswanga ekhanda. Njengamanje, kunezinhlobo ezingaphezu kuka-500 zoshaka eziqashelwayo, eziqoqwe ngezigaba eziningana ezisukela ezinhlotsheni ezincane zasogwini kuya koshaka abakhulu be-pelagic.
Umlando wokuziphendukela kwemvelo waleli qembu mude kakhulu. Amafomu okuqala de peces okufana noshaka olunesihluthuleloAma-acanthodian abizwa ngokuthi ama-acanthodian avele eSilurian Yasekuqaleni, eminyakeni engaphezu kwezigidi ezingu-430 edlule. Kamuva, ngesikhathi seDevonian, kwavela ama-elasmobranch okuqala ngomqondo obanzi, futhi kusukela ngaleso sikhathi kuqhubeke imisebe yayiqhubeka.
Ezinye izinsalela ezidumile, njenge- Otodus megalodon , zibonisa izinga lezi zilwane ezazikwazi ngalo ukulawula ulwandle: kulinganiselwa ukuthi le megalodon yayifinyelela cishe amamitha ayi-16 ubude. Oshaka banamuhla, njengoba sibazi namuhla, balotshwe kusukela eJurassic Yasekuqaleni, eminyakeni engaba yizigidi ezingu-200 edlule, kulandela isikhathi sokuhlukahluka okukhulu.
Izifundo zamuva nje zezakhi zofuzo ziqinisekisile ukuthi oshaka kanye nemisebe yakha i-monophyletic clade (amaNeoselacians), nokuthi ngaphakathi kweSelachii kunezinhlobo ezimbili ezinkulu ze-superorder: iGaleomorphi (ehlanganisa, isibonelo, oshaka abamhlophe, amahlosi noma ama-whale) kanye neSqualomorphi (njenge-angel sharks, i-spiny dogfish noma oshaka abajulile).
Ukuhlukahluka kwezinhlobo nezinhlobo zezindawo zokuhlala
Nakuba sivame ukucabanga ngohlobo olulodwa loshaka, empeleni kunezinhlobo eziningi zezimo, ubukhulu, kanye nendlela yokuphila . Kunezinhlobo ezincane, njenge-dwarf lanternshark ( Etmopterus perryi ), engamasentimitha angaba ngu-17 ubude, kanye neziqhwaga zangempela njenge-whale shark ( Rhincodon typus ), inhlanzi enkulu kunazo zonke emhlabeni, engadlula amamitha angu-12 ubude.
Iningi loshaka lihlala olwandle futhi lihlala cishe kuzo zonke izilwandle, kusukela emanzini angajulile ogwini kuya ekujuleni okungamamitha acishe abe ngu-2000 . Ngaphansi kwamamitha angu-3000, ukuba khona kwabo kuyivelakancane kakhulu, yize ezinye izinhlobo zenkawu enkulu ziqoshwe ekujuleni okungaphezu kwamamitha angu-3500. Zivame ukutholakala emanzini afudumele nashisayo, kodwa kukhona nezinhlobo ezijwayele amanzi abandayo.
Nakuba zihlotshaniswa kakhulu namanzi anosawoti, kunezinye izinto eziphawulekayo ezihlukile. I-bull shark ( i-Carcharhinus leucas ) kanye nabanye oshaka bomfula bohlobo lwe -Glyphis bangahamba baye phezulu futhi balondoloze inani labo emanzini ahlanzekile, ngenxa yokuguquguquka okukhethekile kwesimo somzimba esizoxoxa ngakho kamuva.
Ngokusekelwe endaweni yazo yokuhlala, singahlukanisa amaqembu amakhulu emvelo. Ngakolunye uhlangothi, kukhona oshaka be-pelagic , abahamba olwandle oluvulekile futhi bahamba amabanga amade: leli qembu lihlanganisa ushaka oluhlaza okwesibhakabhaka, ushaka omkhulu omhlophe, ushaka i-mako, kanye noshaka we-oceanic whitetip. Ngakolunye uhlangothi, kukhona oshaka be-reef , abahlotshaniswa nama-coral angajulile noma amatshe angaphansi, njenge-whitetip reef shark, i-grey reef shark, kanye ne-tiger shark.
Kukhona nezinhlobo eziningi zezinhlobo zase-benthic, ezichitha isikhathi esiningi phansi kolwandle. Oshaka abango-Angel, oshaka abakhaphethi, kanye noshaka abahlengikazi bayizibonelo zochwepheshe abahlala phansi, abavame ukuzifihla kahle futhi basebenzisa amasu okuqamekela.
Isakhiwo somzimba esiyisisekelo: uhlaka lwamathambo, isikhumba, kanye namaphiko
Esinye sezici eziphawuleka kakhulu zoshaka ukuthi uhlaka lwawo lune-cartilaginous , hhayi amathambo. I-cartilage inamandla kodwa ilula kakhulu kunethambo, okunciphisa isisindo somzimba futhi kunciphisa izindleko zamandla okunyakaza. Lesi sakhiwo, esihambisana nezicubu eziningi ezixhumanisayo, sibanikeza ukuguquguquka okukhulu.
Imihlathi ifanelwe ukukhulunywa ngokukhethekile. Ngokungafani nezilwane eziningi ezinomgogodla, imihlathi yoshaka ayihlanganiswa nogebhezi . Ukuze imelane nomzamo omkhulu odingekayo wokubamba nokudabula inyamazane, ubuso bomhlathi bunesendlalelo samapuleti amancane, ayisithupha, ane-calcified abizwa ngokuthi ama-tesserae. Ezinhlotsheni ezinkulu njenge-great white shark noma i-tiger shark, kungaba khona izendlalelo eziningana ze-tesserae eziqinisa kakhulu isakhiwo.
Isikhumba simbozwe ngezikali ze-placoid noma ama-denticle esikhumba. I-denticle ngayinye ibunjwe njengezinyo elincane elibheke emsileni, okwenza umzimba ube bushelelezi kusukela ekhanda kuya emsileni futhi ube mahhadlahhadla ngakolunye uhlangothi . La ma-denticle anciphisa ukungqubuzana namanzi, athuthukise i-hydrodynamics, futhi avikele ezifweni ezibangelwa amagciwane kanye nokulimala. Ezinhlotsheni eziningi, ama-denticle ane-pigmentation namaphethini afaka isandla ekufihleni, njengemigqa ye-tiger shark noma amabala e-zebra shark.
Ngokuphathelene nomsila, oshaka abaningi bane -heterocercal caudal fin , lapho i-lobe engenhla ithuthuke khona futhi ikholomu yomgogodla idlulela kuyo. Lokhu kwakheka kudala ukusunduza, futhi ngesikhathi esifanayo, ukuphakama okuqondile okuhlanganisa ukuntanta kwabo okungekuhle. Ezilwaneni ezihamba ngokushesha njenge-porbeagle noma i-mako, i-lobe engezansi nayo inamandla kakhulu okugcina isivinini esikhulu sokuzingelwa.
Ezinye izinhlobo ziye zathatha umsila ngokukhethekile kakhulu, njenge- i-pelagic thresher shark (I-Alopias pelagicus)iphiko layo eliphezulu lomsila lingade njengomzimba wonke futhi lisetshenziswa njengesiswebhu ukuthusa izikole de peces.
Amazinyo, amazinyo kanye nesistimu yokugaya ukudla
Amazinyo oshaka ayindlela ejwayelekile yebhayoloji yasolwandle. Amazinyo awanamathele emathanjeni, kodwa afakwe ezinsinini , ahlelwe ngemigqa eminingana esebenza njengebhande lokuhambisa. Kuyo yonke impilo yawo, ushaka ungalahlekelwa futhi uthathe indawo yamazinyo angamashumi ezinkulungwane.
Ukuma kwamazinyo kashaka kuncike kakhulu ekudleni kwawo. Oshaka abadla ama-crustacean nama-mollusk banamazinyo asicaba, afana ne-molar okuchoboza ngamandla. Labo abagxila ezinhlanzini ezincane bavame ukuba namazinyo amancane, acijile, afanele ukubamba izisulu ezishelelayo. Ezizimbeni ezinkulu zezilwane ezincelisayo zasolwandle, njengoshaka omkhulu omhlophe, amazinyo angaphezulu angunxantathu futhi anezinsika, afanelekela ukusika izingcezu ezinkulu zenyama, kuyilapho amazinyo aphansi esetshenziselwa ukubamba.
Ezinhlotsheni ezidla izihlungi njenge-whale shark noma i-basking shark, amazinyo mancane futhi acishe abe uphawu ; indima eyinhloko idlalwa yi-gill rakers, izakhiwo ezinde nezincane ezisebenza njengesihlungi sokugcina i-plankton nezinhlanzi ezincane ngenkathi amanzi edlula ezihlungini.
Uhlelo lokugaya ukudla lubonisa ukuzivumelanisa nezimo okumangalisayo. Isisu esinomumo ofana no-J singakhukhuleka ukuze sigcine ukudla okuningi. Uma ushaka udle into engafanele (amathambo amakhulu, izinto zangaphandle), uyakwazi ukugudluza isisu sakhe kancane, asiphendule ngaphakathi bese ekhipha okuqukethwe ngomlomo wakhe.
Amathumbu mafushane, kodwa ngaphakathi kwawo aqukethe i -spiral valve , uhlobo "lwe-spiral slide" olwandisa kakhulu indawo yokumunca ngaphandle kwesidingo sepayipi elide kakhulu. Ngenxa yalesi sakhiwo, ukudla kuhamba kancane futhi izakhamzimba zimuncwa kahle ngangokunokwenzeka ngaphambi kokuba imfucuza ifinyelele ku-cloaca.
Ukuphefumula, ukujikeleza kwegazi, kanye nokuthamba
Njengazo zonke izinhlanzi, oshaka bathola umoya-mpilo uncibilika emanzini ngokusebenzisa ama-gill abo, kodwa uhlelo lwabo lunezici ezithile ezihlukile. Ngokungafani nezinhlanzi ezinamathambo, ama-gill slits awamboziwe yi-operculum ; kunalokho, abonakala njengemifantu evulekile ngemuva kwekhanda. Izinhlobo eziningi zinembobo encane etholakala ngemuva kweso, ewusizo kakhulu ekumunceni amanzi lapho oshaka ephumule phansi kolwandle.
Uma uhamba, amanzi angena ngomlomo bese egeleza phezu kwamagill ngenqubo ebizwa ngokuthi i-ram ventilation. Iningi loshaka liyakwazi futhi ukupompa amanzi ngemisipha yalo yomphimbo uma liphumule. Kodwa-ke, ezinye izinhlobo ze-pelagic ezikhuthele kakhulu zilahlekelwe yileli khono futhi zibhekwa "njengeziphephethamoya ezibophezelekile": uma ziyeka ukubhukuda, ukugeleza kwamanzi kuyayeka futhi zingase ziminyane.
Uhlelo lokujikeleza kwegazi lulula kakhulu: inhliziyo enamakamelo amabili iphampa igazi elikhishwe umoya-mpilo liye ezimbotsheni zokuphefumula nge-ventral aorta, lapho lifakwa khona umoya-mpilo bese libuya nge-dorsal aorta ukuze lisatshalaliswe emzimbeni wonke. Ukusuka lapho, libuyela enhliziyweni ngemithambo yegazi emikhulu, liqedele umjikelezo.
Ngokuphathelene nokuntanta, oshaka abanaso isinyi sokubhukuda esigcwele igesi, njengabaningi de peces ithambo. Esikhundleni salokho, Zinesibindi esikhulu, zicebile ngamafutha aphansi, ikakhulukazi i-squalene. Lesi sitho singamelela kufika ku-30% wobunzima bomzimba futhi sisebenza njengendawo yokugcina amandla kanye nesakhiwo sokuntanta kancane. Noma kunjalo, ukuntanta kwaso kuhlala kungalungile, futhi sithembele kakhulu ekunyakazeni kanye nesimo samaphiko aso ukuze silondoloze ukujula okufunwayo.
Ezinhlotsheni ezichitha isikhathi phansi, njenge-nurse shark, lokhu kuntanta okungekuhle kuyinzuzo ngisho nangokwengeziwe, njengoba kubavumela ukuthi baphumule kalula endaweni engaphansi komhlaba. Amanye ama-shark, uma ephendulwe abheke phansi noma eshaywa yimpumulo yawo, angena esimweni sokungakwazi ukuhamba kahle okwenziwa abacwaningi ukuze bawaphathe ngokuphepha.
I-Physiology: izinga lokushisa, i-osmoregulation, kanye ne-chemistry yangaphakathi
Iningi loshaka liyizilwane ezinegazi elibandayo noma eziphila nge-poikilothermic, okusho ukuthi izinga lokushisa lomzimba wazo liseduze nelamanzi azungezile . Kodwa-ke, ezinye izinhlobo ezingomndeni wakwaLamnidae, njenge-great white shark noma i-mako, ziyakwazi ukugcina izicubu ezithile emazingeni okushisa aphezulu ngenxa yesistimu yokushintshana kokushisa ehambisanayo (i-rete mirabile) kanye nemisipha ebomvu etholakala ngaphakathi kwemizimba yazo.
Ukulawulwa kosawoti namanzi nakho kuhlukile. Izicubu zoshaka ziqukethe amazinga aphezulu e-urea kanye ne-trimethylamine N-oxide (TMAO) , okwenza uketshezi lomzimba wazo lucishe lube yi-isotonic ngamanzi olwandle. Lokhu kuzivumela ukuthi zigweme ukulahlekelwa amanzi ngokweqile ngenxa ye-osmosis, kodwa kwenza impilo yazo ibe nzima emanzini ahlanzekile, lapho zingathola khona amanzi amaningi futhi zilahlekelwe usawoti omningi kakhulu.
Uma ushaka ufa, i-urea ihlukaniswa ibe yi-ammonia ngesenzo samagciwane, okuchaza iphunga elinamandla le-ammonia lezidumbu ezibolayo . Zine-rectal gland ekhethekile ekhipha ama-chloride, okuyisihluthulelo sokuqedela ibhalansi kasawoti.
Ukugaya ukudla kulezi zilwane kungaba kancane. Ngemva kokudlula esiswini nasemathunjini ajiyile, izinsalela ezingagayiwe ekugcineni zikhishwa nge-cloaca . Lokhu kuhamba kancane kokugaya ukudla, kuhlanganiswe nesu lazo lokuzingela, kusho ukuthi akudingeki zidle nsuku zonke; ezinye izinhlobo zingahlala isikhathi eside zingadli ngemva kokudla okukhulu.
Izinzwa zoShark: zibukhali kakhulu kunalokho ocabanga
Okwenza oshaka babe ngabakhethekile yizinzwa zabo eziningi. Banezinzwa zokuhogela ezithuthuke kakhulu, ukubona, ukuzwa, ukunambitha, kanye nokuzwela komshini, kodwa futhi banekhono elengeziwe: ukwamukela ngogesi . Konke lokhu kubenza babe yizilwane ezidla ezinye ezisebenza kahle kakhulu, ngisho nasemanzini amnyama noma ebumnyameni obuphelele.
Iphunga futhi unambitha
Oshaka banayo amabhalbhu okunuka athuthukiswe kakhulu zixhunywe emakhaleni ahlukene nomlomo. Ziyakwazi ukubona amazinga amancane ezinto ezithile, njengezinhlanganisela ezikhona egazini. de peceskanye nokuthola indlela iphunga eliya ngayo ngokuqhathanisa isikhathi elifika ngaso ekhaleni ngalinye.
Ubukhulu obuhlobene bebhalbhu yephunga buyahlukahluka kuye ngendawo ezungezile. Emanzini angabonakali kahle, oshaka bavame ukuthembela kakhulu emuzweni wabo wokuhogela , kanti emadwaleni akhanyiswe kahle ezinye izinhlobo zinciphisa ukuthembela kwazo kulo mqondo futhi zithembele kakhulu ekuboneni. Izinhlobo zasemanzini ajulile, lapho ukukhanya kungangeni khona kalula, ziphinde zibe nezakhiwo ezinkulu zephunga.
Ngokuphathelene nokunambitha, oshaka banezinzwa zokunambitha emlonyeni wabo (hhayi ezilimini zabo, ngoba abanazo). Izinhlungu zabo zizwela kakhulu emafutheni , okunengqondo uma ubheka ukuthi badinga ukudla okunamandla kakhulu. Bavame ukuluma okuthile, bakunambithe, futhi uma kungahlangabezani nokulindela kwabo, bamane bakukhafule.
Umbono kanye ne-bioluminescence
Ngokuphambene nenkolelo evamile, oshaka abazona izilwane "ezingaboni kahle". Isakhiwo samehlo abo sifana nesezinye izilwane ezinomgogodla , sinelensi, i-cornea, ne-retina. Ngaphezu kwalokho, bane-tapetum lucidum, ungqimba olukhanyayo ngemuva kwe-retina olushaya ukukhanya futhi luthuthukisa kakhulu ukubona ekukhanyeni okuphansi.
Iningi lezinhlobo ezicwaningiwe libonakala linombono omnyama nomhlophe noma ububanzi bemibala obulinganiselwe kakhulu, njengoba ama-retina amaningi enezinduku noma uhlobo lwekhoni oluzwela oluhlaza. Lokhu kusikisela ukuthi ukungafani kubaluleke kakhulu kunombala kuzo lapho kutholwa inyamazane noma izithiyo.
Amanye ama-shark ane-membrane ehlabayo, ijwabu leso elibonakalayo noma elingacacile elivala ukuvikela iso ngesikhathi sokuhlaselwa . Ezinye izinhlobo, njenge-great white shark, azinalo lolu lwebu futhi esikhundleni salokho zijika amehlo azo emuva lapho zihlasela ukuze zigweme ukulimala.
Isici esithakazelisayo soshaka abathile, njenge- catshark noma i-pufferfish , yi-biofluorescence. Ngaphansi kokukhanya okuluhlaza okwesibhakabhaka, izingxenye zesikhumba sabo zikhipha imibala eluhlaza ngenxa yamakhemikhali e-fluorescent atholakala ekusetshenzisweni kwama-asidi njenge-kynurenic acid. Leli khono kucatshangwa ukuthi lisebenza ekufihleni noma ukuxhumana phakathi kwabantu ngabanye.
Umugqa wendlebe nowecala
Nakuba zingenazo izindlebe zangaphandle, oshaka banezimbobo ezincane emakhanda abo eziholela endlebeni yangaphakathi . Zizwela kakhulu imisindo ephansi, njengaleyo ebangelwa ukunyakaza okungazelelwe noma izilwane ezilimele, ezingazithola zikude ngamamitha angamakhulu.
Okuhlobene nendlebe uhlelo lwemigqa eseceleni, uchungechunge lwemisele egcwele uketshezi egijima ubude bomzimba equkethe ama-neuromast (amangqamuzana ezinwele) azwela ukudlidliza kanye noshintsho lwengcindezi. Lo "mqondo wesithupha wemishini" ubavumela ukuthi babone imisinga, izithiyo, kanye nesilwane ngisho nangaphandle kokuthintana ngamehlo, ngokuzwela okusebangeni lama-25 kuya kwangama-50 Hz.
Ukwamukelwa kwe-Electro: i-ampullae yaseLorenzini
Mhlawumbe ikhono elimangalisayo kakhulu lezinzwa zoshaka ukwamukela ngogesi. Esifundeni sempumulo kanye nasekhanda, kunamakhulu noma izinkulungwane zama -ampullae eLorenzini , izitho ezincane ezixhunywe ngaphandle yizimbobo ezigcwele ijeli elihambisa umoya.
Lezi zitho zibona amasimu kagesi amancane akhiqizwa umsebenzi wemisipha nowemizwa wezinye izilwane. Ngenxa yalokhu, ushaka ungathola inyamazane egqitshwe esihlabathini noma efihliwe ebumnyameni obukhulu . Ngaphezu kwalokho, kubonakala sengathi zibona amasimu kagesi abangelwa yimisinga yolwandle ensimini yamagnetic yoMhlaba, into engabasiza ukuthi baziqondise futhi bathathe uhambo olude.
Ukuziphatha, impilo yomphakathi, kanye nokunyakaza
Sekuyisikhathi eside, oshaka babecatshangwa ukuthi bangabantu abazingelayo bodwa futhi abangazi lutho , kodwa izifundo zanamuhla zembula iqiniso eliyinkimbinkimbi kakhulu. Kuye kwachazwa amaqembu oshaka abaningi noma amakhulu, kanye nezigaba phakathi kwezinhlobo nangaphakathi kwazo, ngisho nokuziphatha okufana nokudlala.
Ezinye izinhlobo, njenge-scalloped hammerhead shark, zihlangana ngamaqembu amakhulu eduze kwezintaba noma iziqhingi. Ngaphakathi kwalezi zinhlanganiso, akuzona zonke izilwane ezihlala endaweni efanayo noma eziziphatha ngendlela efanayo , okuphakamisa izindima ezahlukene zomphakathi. Ezimweni zokudla, kuye kwabonakala ukubusa okucacile: isibonelo, oshaka abamhlophe basolwandle banganqoba oshaka abasilika abanobukhulu obufanayo.
Ukunyakaza kwazo okufudukayo nakho kuyamangaza. Oshaka abaningi be-pelagic bahamba izinkulungwane zamakhilomitha minyaka yonke , bewela izizinda zolwandle ukuze bazale, bondle, noma basebenzise izimo zemvelo ezinhle. Imizila yabo ingaba yinkimbinkimbi kakhulu kunalokho esikucabangayo, lapho kunezindawo ezibalulekile zokuma ezindaweni ezicebile ngezilwane ezidla inyama.
Ngokuphathelene nesivinini, oshaka abaningi bahamba ngesivinini esilinganiselwe, cishe amakhilomitha ayi-8 ngehora, okwanele ukuqapha indawo yabo. Kodwa-ke, ezinye izinhlobo zifinyelela isivinini esimangalisayo : i-shortfin mako ingafinyelela cishe amakhilomitha angama-50 ngehora, kanti i-great white shark nayo idlula isivinini esifanayo lapho ihlasela.
Umsebenzi wansuku zonke uhlanganisa izigaba zokunyakaza okusebenzayo nezikhathi zokuphumula okubonakalayo. Kuye kwaboniswa ukuthi ezinhlotsheni ezifana ne-spiny dogfish, intambo yomgogodla iyakwazi ukuxhumanisa ukubhukuda ngisho nalapho ubuchopho busesimweni sokusebenza okuphansi , okuphakamisa uhlobo "lokubhukuda ubuthongo."
Ukondla: kusukela ezihlanzini ezinkulu kuya ezihlanzini ezihlaselayo
Ukudla koshaka kuhlukahlukene kakhulu, yize iningi labo liyizilwane ezidla inyama. Kuye ngohlobo lwezilwane, zingondla de peces izidalwa ezincane, ama-cephalopod, ama-crustacean, ama-bivalves, izimfudu, izinyoni zasolwandle, noma izilwane ezincelisayo zasolwandleLokhu kuhlukahluka kwezilwane ezidla inyama kubonakala ngqo ekwakhekeni kwazo kanye namasu azo okuzingela.
Phakathi kwezindawo zokondla izihlungi ezinkulu kukhona i-whale shark, i-basking shark, kanye ne-megamouth shark. Ngayinye iye yasungula indlela ehlukile yokuhlunga i-plankton : i-whale shark ithembele ekumunceni amanzi amaningi ngenkuthalo, i-basking shark ibhukuda ngomlomo wayo uvulekile, ivumela amanzi ukuba ageleze, kanti i-megamouth shark ihlanganisa ukumunca nezakhiwo ze-bioluminescent emlonyeni wayo ezingadonsela inyamazane emanzini ajulile.
Ngakolunye uhlangothi lomkhakha sinochwepheshe abafana no- umsiki wamakhukhi kashaka, edabula amadiski amancane enyama de peces kanye nezilwane zasolwandle ezinkulu kakhulu. Amazinyo azo aphansi amakhulu, abukhali njengensingo afanelekela ukuxhuga nokusonta umzimba, edabula ingcezu yezicubu.
Ezinye izinhlobo eziningi zezilwane zase-benthic, njenge-angel sharks kanye ne-carpet sharks, ziyazifihla phansi kolwandle futhi zibe yizilwane ezidla ezinye. Zilinda zinganyakazi kuze kube yilapho inyamazane idlula eduze ngokwanele , bese zivula imilomo yazo ngomsindo, zikhiphe ukumunca okunamandla okugwinya konke.
Oshaka abasebenzisa ama-reef noma ama-coastal shark bavame ukuzingela izinhlanzi, ama-cephalopod, noma ama-crustacean. Kwezinye izimo, njenge-whitetip reef shark, lokhu kuye kwabhalwa phansi. ukuzingela kweqembu ngokubambisanaamabhange asemakhoneni de peces noma ukuphoqa inyamazane ukuba iphume emifantwini nasemaphangweni.
Kukhona ngisho nohlobo olwaziwayo lwe-omnivorous, i- bonnethead shark , oluthi, ngaphezu kwezilwane zasolwandle ezingenamgogodla kanye nezinhlanzi ezincane, ludle inani elikhulu lotshani basolwandle futhi lukwazi ukusebenzisa cishe ingxenye yezakhamzimba zezitshalo oluzidlayo.
Ukuzala: amasu, izinhlobo zentuthuko kanye nokuhlanganiswa
Ngokungafani nezinhlanzi ezivamile ezibekela amaqanda ayizinkulungwane futhi zingawanakekeli kahle, oshaka balandela isu lokuzala lohlobo lwe-K . Lokhu kusho ukuthi bakhiqiza inzalo encane, ekhule kahle futhi enethuba eliphezulu lokusinda, kodwa kuthatha isikhathi eside ukufinyelela ekuvuthweni ngokocansi. Kugxile ekhwalithini kunobuningi, kusebenza kakhulu ezindaweni ezizinzile kodwa okwenza kube sengozini yokudoba ngokweqile.
Ukuvundisa kungaphakathi. Abesilisa bane-claspers, noma i-pterygopodia , emaphikweni abo e-pelvic, abawafaka esibelethweni sowesifazane ukuze badlulisele isidoda. Ukuhlangana, okunzima ukukubona endle, kuvame ukuhilela ukuzibamba ngokuluma, kuze kube seqophelweni lokuthi kwezinye izinhlobo zabesifazane baye baba nesikhumba esijiyile ezindaweni ezithile ukuze bamelane nalezi zibonakaliso zothando ezinzima.
Kuye ngohlobo, ukukhula koshaka abasebasha kungalandela izindlela ezintathu eziyinhloko: i-oviparity, i-ovoviviparity, kanye ne-viviparity. Kushaka be-oviparous , insikazi ibeka ama-capsules amaqanda anesikhumba, aziwa kakhulu ngokuthi "izikhwama ze-mermaid," anamathele ku-algae noma imifantu. I-embryo eyodwa noma ngaphezulu ikhula ngaphakathi futhi iqhamuselwe ngaphandle komzimba kamama; lokhu kuyinto evamile kuma-catshark amaningi kanye ne-Port Jackson shark.
I-Ovoviviparity, evame kakhulu phakathi koshaka, ihilela amaqanda asele ngaphakathi kwe-oviduct , kanye namantshontsho adla i-yolk kanye nokuphuma kwesibeletho kuze kube yilapho ezalwa ephelele. Kwezinye izinhlobo ze-lamniforms, i-oophagy iyenzeka (ama-embryo akhule kakhulu adla amaqanda asele), ngisho nokudla isilwane ngaphakathi kwesibeletho, njengaku-sand tiger shark, lapho amantshontsho anamandla kakhulu edla khona abafowabo nodadewabo abasakhula.
Ekuphileni kwangempela, kwakheka isakhiwo esifana ne-placenta , esixhumanisa umbungu nonina futhi sivumela ukushintshaniswa kwezakhamzimba okufana nokwezilwane ezincelisayo. Lokhu kunjalo ngoshaka abaningi be-hammerhead, oshaka be-bull, kanye nezinhlobo zohlobo lwe- Mustelus . Amaphuphu azalwa ekhuthele futhi ezimele, ekwazi ukuzimela kusukela ngosuku lokuqala.
Izikhathi zokukhulelwa zingaba zinde kakhulu. Izinhlanzi ezincane ezinamahlumela, isibonelo, zinesikhathi sokukhulelwa esingafika ezinyangeni ezingu-24 , futhi kusolwa ukuthi zinde nakakhulu kuma-shark ahlala e-basking kanye nama-frilled shark. Ngenxa yalokho, abesifazane abaningi bazala njalo eminyakeni embalwa, okunciphisa kakhulu ukubuyiswa kwenani labantu.
Isenzakalo esimangalisayo esilotshwe ezindaweni zokugcina izithombo zasolwandle nakwezinye izimo endle yi -parthenogenesis : abesifazane abakhiqiza inzalo ngaphandle kokuxhumana kwakamuva nabesilisa noma noma yimuphi umnikelo wezakhi zofuzo woyise otholakalayo. Zonke izinkomba zisikisela ukuthi kuyisisombululo esiphuthumayo lapho kungekho mngane otholakalayo, kodwa kunciphisa ukuguquguquka kwezakhi zofuzo futhi, ngokuhamba kwesikhathi, kungenza buthaka imiphakathi.
Ngaphezu kwalokho, kuye kwachazwa amacala amaningana okuxutshwa kwemvelo phakathi kwezinhlobo ezihlobene eduze emashumini eminyaka amuva nje, njengaphakathi kweCarcharhinus tilstoni neCarcharhinus limbatus , noma phakathi koshaka abahlukene be-hammerhead. Lawa ma-hybrid angamelana kakhulu nezinguquko zemvelo futhi ekugcineni athathe indawo yezinhlobo zawo zabazali endaweni, yize umthelela wawo wangempela usacwaningwa.
Ubude besikhathi kanye nesivinini sempilo
Isikhathi sokuphila siyahlukahluka kakhulu kuye ngohlobo, kodwa oshaka abaningi baphila phakathi kwamashumi amabili namashumi amathathu eminyaka . Nokho, kukhona "ogogo nomkhulu bangempela bolwandle": i-spiny dogfish ingadlula kalula iminyaka eyi-100, kanti i-whale shark nayo ibonakala sengathi iphila iminyaka engaphezu kwekhulu.
Ushaka waseGreenland ( i-Somniosus microcephalus ) uphethe irekhodi lesilwane esinomgogodla esidala kunazo zonke ezaziwayo . Ukuhlolwa kosuku lwe-radiocarbon lwamalensi amehlo aso kwembule amasampula aneminyaka engaphezu kuka-270 ubudala, kanti izilinganiso zisikisela iminyaka ecishe ibe ngu-400 kwabanye abantu abakhulu. Lokhu kusho ukuthi abanye kungenzeka ukuthi bazalwa ngaphambi kweNguquko yaseFrance.
Lo mjikelezo wokuphila ohamba kancane kakhulu, kuhlanganiswe nokuvuthwa kobulili sekwephuzile kanye nokuzala okuncane, kuchaza ukuthi kungani inani loshaka lincipha ngokushesha kangaka lapho ingcindezi yokudoba ikhuphuka futhi, ngokuphambene nalokho, kuthatha isikhathi eside kakhulu ukululama ngisho nalapho kusetshenziswa izinyathelo zokuvikela eziqinile.
Oshaka nabantu: ukuhlaselwa, izinganekwane kanye nokuhlala ndawonye
Njalo uma kuhlaselwa ushaka, kuba sematheni emhlabeni wonke, kodwa uma sibheka izinombolo ezibandayo neziqinile, isithombe sishintsha kakhulu. Ezinhlotsheni ezingaphezu kuka-500 ezichazwe, zimbalwa kuphela eziye zaba necala lokuhlasela okubulalayo okungabangelwanga : ushaka omkhulu omhlophe, ushaka we-tiger, ushaka we-bull, kanye noshaka we-whitetip wasolwandle.
Ifayela Lokuhlasela Koshaka Lamazwe Ngamazwe liqopha, ngokwesilinganiso, ukufa kwabantu abangaphezu kweshumi nambili ngonyaka emhlabeni wonke ngenxa yokuhlaselwa okungacasuliwe, uma kuqhathaniswa nezinye izimbangela zokufa olwandle (ukuminza, izingozi zesikebhe) ezivame kakhulu. Noma kunjalo, isithombe sikashaka "njengomuntu odla abantu" sesigxile kakhulu emcabangweni ohlangene, ikakhulukazi ngenxa yamafilimu afana nendaba ethi "Jaws".
Ucwaningo lubonisa ukuthi ekuhlaselweni okuningi, ushaka ungase uphambanise umbhukudi noma umgibeli we-surfer njengesisulu sakhe esivamile , njenge-seal. Akuvamile ukuthi ushaka ukhulule isisulu sawo ngemva kokulunywa kokuqala, eqaphela ukuthi "awazi ukuthi ulindeleni." Ezindaweni eziningi lapho abantu noshaka babelana khona indawo efanayo, ukuhlala ndawonye kuyinto yansuku zonke futhi akukho zingozi.
Kunezincomo ezilula zokunciphisa ingozi: gwema ukubhukuda ekuseni nakusihlwa ezindaweni ezaziwa ngokuba khona koshaka abakhulu abadla ezinye izilwane, ungangeni emanzini unezilonda eziphuma igazi noma ubucwebe obucwebezelayo obubonisa ukukhanya okufana namaxolo ezinhlanzi, futhi ungachithi kakhulu ezindaweni lapho oshaka bedla khona.
Ngokumangalisayo, nakuba ezinye izici zesiko elidumile zibenza babe yihlazo oshaka, amasiko amaningi endabuko aye abahlonipha. EHawaii, isibonelo, kukhona oshaka be-aumakua, imimoya yabanakekeli bomndeni; izinganekwane zasePolynesia naseSamoa zigcwele izindaba zabantu abaguqulwe baba oshaka kanye nonkulunkulu abafana noshaka.
Ubudlelwano nokudoba, ukuhlikihla amafindo kanye nokulondolozwa kwemvelo
Uma sibheka umthelela ovela kolunye uhlangothi, isithombe sibi kakhulu; umthelela wokudoba oshaka mkhulu kakhulu. Kulinganiselwa ukuthi, emashumini ambalwa eminyaka edlule kuphela, cishe oshaka abayizigidi eziyi-100 bayafa minyaka yonke ngenxa yemisebenzi yabantu, kungaba ngenxa yokudoba okuqondiwe, ukubanjwa ngengozi, noma ukushaywa ngamaphiko. Izifundo zibonisa ukwehla komhlaba wonke cishe ngo-70% kwenani loshaka basemanzini kanye ne-ray eminyakeni engu-50 edlule.
Ukugoba amafindo oshaka kungenye yezinsongo ezibonakala kakhulu neziphikisanayo. Kuhlanganisa ukunquma amafindo oshaka, ngokuvamile esaphila, nokuphonsa isidumbu emuva olwandle . Ngenxa yokuthi amafindo abiza amanani aphezulu kakhulu emakethe (ikakhulukazi e-Asia ngesobho lamafindo oshaka), izikebhe eziningi zikhetha ukugcina le ngxenye yesilwane kuphela, zichitha okusele.
Ngaphandle kwamaphiko, inyama yoshaka idliwa emazweni amaningi futhi isetshenziswa ezitsheni zendabuko, ngezinye izikhathi ngamagama ajwayelekile njenge-"whitefish" noma "flake." Ukusetshenziswa kwe-cartilage nezinye izinto ezitholakala kuyo kuye kwakhuthazwa njengemithi yokwelapha umdlavuza noma i-osteoarthritis, kodwa izifundo zesayensi azisekeli lezi zakhiwo futhi ziyaxwayisa ngokuba khona kwezinto ezingcolisayo njenge -mercury noma i-neurotoxins (isibonelo, i-BMAA) kweminye imikhiqizo.
Enye inkinga enkulu ukubanjwa koshaka njengengxenye yezinyathelo "zokulawula" zokunciphisa ukuhlaselwa. Izinhlelo ze-net kanye ne-drum line ezindaweni ezifana neQueensland neNew South Wales (e-Australia), KwaZulu-Natal (eNingizimu Afrika), kanye neRéunion Island zibulale amashumi ezinkulungwane zoshaka, kanye namahlengethwa, izimfudu, imisebe, nezinye izinhlobo ezingezona ezihlosiwe, ngaphandle kobufakazi obucacile bokuthi zinciphisa ngempumelelo ingozi kubabhukudi.
Ngenxa yalesi simo, kuye kwavela izinhlelo ezibalulekile emashumini eminyaka amuva nje: ukuvinjelwa kokwenza amafin emanzini e-European Union nakwamanye amazwe ahlukahlukene, imithetho yezwe e-United States evimbela ukuhweba ngamafin, kanye nokudalwa kwezindawo zokugcina oshaka ezindaweni ezifana neBahamas, iPalau, iziQhingi zaseCook, amazwe amaningana asePacific noma izindawo zaseMaldives.
Uhlu Olubomvu lwe-IUCN seluvele lubheka ingxenye enkulu yezinhlobo zoshaka kanye ne-ray njengezisengozini , eziningi zazo ezisezigabeni eziphezulu njenge "ezisengozini" noma "ezisengozini enkulu." Izinhlangano ezifana ne-CITES zengeze izinhlobo eziningana eziwusizo kwezentengiselwano (oshaka be-hammerhead, oshaka be-oceanic whitetip, oshaka be-shortfin mako) ezithasiselweni zazo, okusho ukuthi ukudoba kwazo kanye nokuhweba kwamanye amazwe kudinga izimvume kanye nokulawula okuqinile.
Konke lokhu kubonisa iqiniso elingenakuphikwa: ngaphandle koshaka, azikho izilwandle ezinempilo . Njengezilwane ezidla ezinye izilwane, zilawula inani lezilwane ezizingelayo, zivimbele ukwanda kwezilwane ezigulayo noma ezibuthakathaka, futhi zigcina isakhiwo semiphakathi yasolwandle. Ukuzivikela akuyona nje indaba yokuziphatha, kodwa kuyisidingo esibalulekile semvelo.
Ibhayoloji yoshaka basolwandle yembula iqembu lezilwane ezizivumelanise kahle kakhulu, ezine-anatomy, izinzwa, kanye nokuziphatha okulungiswe kahle ukuze kuhambisane nokuphila olwandle oluvulekile nasemadwaleni. Ukuqonda indlela imizimba yazo esebenza ngayo, indlela ezisebenzisana ngayo, indlela ezidla ngayo, kanye nendlela ezizala ngayo kuyisinyathelo sokuqala sokuxazulula izinganekwane, ukwazisa indima yazo ezindaweni zemvelo, nokuvuma ukuthi ikusasa lazo lincike kakhulu kulokho esikwenzayo—noma esihluleka ukukwenza—emashumini eminyaka ezayo.
