Izinhlanzi ezinamazinyo, izinhlanzi ezinobuthi: isici, isakhiwo, umehluko

Ngokusho kwedatha yakamuva yesayense, okhokho balezinhlanzi zanamuhla - izilwane zasendle ezifana nezibukeka - zazihlala zikhona ekuqaleni kweCambrian, cishe eminyakeni eyizigidi ezingu-530 edlule. Kunconywa ukuthi izidalwa ezifanayo ezitholakale ngo-1999 esifundazweni saseYunnan zingaba yizifuba zezilwane eziphilayo.

Okwamanje, izinhlanzi ezinamazinyo, ama-bony fish (ama-lobateperes nama-luchepers) aziba ngaphezu kwengxenye yazo zonke izilwane eziphilayo eziphila emhlabeni. Kuphelele, kunezinhlobo ezingaba yizinkulungwane ezingu-31 zezinhlobo ezihlukahlukene, ubukhulu, abahlala emanzini anosawoti namanzi ahlanzekile. Ukutadisha izidalwa zasendulo kuyisayensi ehlukene - ichthyology. Masihlale eminye imininingwane emakilasi, izici zabo kanye nokungafani.

Izinhlanzi ezinomdlavuza

Isici esiyinhloko sabo bonke abamele ekilasini ukuthi ama-squelettes abo anama-cartilages, okwathi ngesikhathi sokubanjwa kwamaminerali kungaba nzima kakhulu. Ngaphambi kwalesi sizathu, babhekwa njengezilwane zasendulo. Kodwa-ke, iningi lazo libhekwa ngokuzalwa okuphilayo, ngezinye izikhathi ngisho nokubunjwa kwe-bile placenta - yilokho izinhlanzi eziqhamukayo ezihlukeneyo ezihlukana ne-bone fish cardinally.

Ngaphezu kwalokho, banezici eziningana zezici zesakhiwo. Okokuqala, ukungabi khona kwesambiso sokubhukuda. Ngakho-ke, kufanele bathuthele ukuze behlele phansi emgodini. Okwesibili, izinhlanzi ezinamaqabunga azikho ikhava yegill, futhi izigulane zivulekile ngaphandle ngezikhala zomuntu. Okwesithathu, konke kuhlanganiswe izikali ze-placoid, ezifana namazinyo ezilwanyana eziphilayo. Iqukethe i-dentin ne-koqweqwe lwawo ukumboza. Izikali ezinjalo azibuyiselwe ngokulahlekelwa, kodwa ngokukhula kwenhlanzi inani lalo landa.

Izinhlelo zokusekela impilo ezinhlanzini ezihamba phambili

Izimpawu zezinhlanzi ezinamazinyo ezingapheli nezithambo ngeke ziphelele, uma kungenjalo ukukhuluma ngezinhlelo eziyinhloko: ukujikeleza kwegazi, ukugaya ukudla nokulala ngokocansi, lapho kukhona umehluko. I-cartilage inegazi elibomvu (ngenxa yokutholakala kwe-hemoglobin ne-erythrocytes), eyenziwa yi-spleen. Uhlelo lwe-circulatory ngokwayo lufana nolwase-cyclostomes. Hlangana nomgogodla wehliswa ngesimo seenhlanzi ezimbili ezibomvu zezinso. Umathumbu wezinhlanzi ezinamazinyo ezinamazinyo aqukethe izingxenye ezintathu: isisu esisinyameni nesincane, i-rectum. Isibindi nama-pancre asethuthukile kahle. Kodwa into ebaluleke kakhulu ukuthi izinkambiso zezinhlanzi ze-cartilaginous ne-Bony izinhlanzi ziyahlukahluka ohlelweni lwesimiso sokuzala. Okokuqala kubonakala ngokufaka umquba wangaphakathi nokwakheka kweqanda, okungafakwa endaweni yangaphandle noma ukuhlala engxenyeni engezansi ye-oviduct. Esimweni sesibili, umbungu uqala ukukhula emzimbeni womama.

Ukuhlukaniswa kwezinhlanzi ezinamandla

Bonke abamele abakhona bezinhlanzi zezinhlanzi zeCartilaginous bahlukaniswa baba yizibalo ezintathu.

• Ama-skates ayizinhlanzi ezinobuthi (i-bony fishes - ngemuva kwalokhu) enezici zomzimba "ezithwetshiwe" kanye nezinhlawulo ezinkulu zepectoral ezifakwe nekhanda. Izilinganiso ziyancishiswa eziningi zazo, Omunye wabamele abakhulu kunazo zonke i-manta.
• AmaSharki. Inhlanzi, enezici ezinjalo ezihlukile: umzimba ohlotshiswe nge-torpedo, i-cauperocercal enkulu ye-caudal fin fin kanye nenani elikhulu lamazinyo emilenzeni. Omunye wabamele abakhulu kunazo zonke emhlabeni, okhokho babo abavela eminyakeni engu-420-450 eminyakeni edlule. Ubukhulu bungaba ngu-17 cm kuya ku-20 m (i-whale shark - esithombeni ngenhla), izilwane eziningi. Inhlobo ngayinye inezinsuku ezithile zokuphila, kodwa ezimweni eziningi ziphila isikhathi eside - iminyaka engu-20-30.
• I-Tselnogolovye - imele iphiko elilodwa kuphela - i-Chimera, ehlanganisa izinhlanzi ezingaba ngu-50 ikakhulukazi ezinhlanzi. Lokhu kuchaza isifundo sabo esincane.

Inhlanzi ye-Bony: isici esijwayelekile

Sekuyisikhathi eside, kuze kube sekhulwini lama-21, izinhlanzi ezinamazinyo, izinhlanzi zezinhlanzi zazibhekwa njengezigaba ezimbili. Kodwa-ke, esimweni sesayensi, elinye iphuzu lokubheka lithola ukwamukelwa kabanzi. Ngakho-ke, isazi sezokwelapha saseCanada emisebenzini yakhe ye-lobe-hoppers kanye ne-ray-finned fish ichaza ngezigaba ezihlukene, futhi ithambo, ngokulandelana, lingena e-superclass. Lesi yisakhamuzi esihluke kakhulu kuzo zonke izinhlobo zamanzi. Imilomo yabo yenziwa ngokubamba amahlombe namazinyo aphezu kwawo, izigulana zitholakala emagqumeni e- branchial, futhi amathanga ahlanganiswe.

Umehluko ezivela ezinhlanzi ezinamazinyo

Umehluko obaluleke kunazo zonke phakathi kwezinhlanzi zezinhlanzi ne-cartilaginous kucacile egameni - i-skeleton. Wenziwe ngamathambo. Esikhathini sangaphakathi isistimu yokujikeleza, ukufihla, ukukhiqiza nokugaya. Izikali nazo ziyizici, enye yezinhlobo ezintathu: i-cycloid, i-ctenoid noma i-ganoid.

Umehluko olandelayo ukutholakala kwesinye isibopho esingaphansi komgogodla futhi sigcwaliswe ngegesi ezifihla izitsha zegazi. Njengoba ukwanda kwevolumu yayo, inhlanzi ihamba kalula, futhi iyancipha - iya ekujuleni.

Ukungafani akuwona nje kuphela izimpawu zangaphandle zezinhlanzi ezinamazinyo kanye nezinhlanzi, kodwa nezitho zokuzala, njengoba sekushiwo kakade. Kwabaningi abameleli beqembu lesibili, ukukhulelwa kwangaphandle kwenzeka emvelweni wamanzi. Le nqubo ibizwa ngokuthi iyakhula, kwenzeka ngezikhathi ezithile futhi ihambisana nokuziphatha komlingiswa.

Izinhlanzi ezihlanziwe

Leli klasi elibaluleke kakhulu ezinhlobonhlobo zanhlanzi zanamuhla, zibala izinhlobo ezingaphezu kweziyizinkulungwane ezingu-20, okungaba ngu-95%. Zithinta zonke izingxenye zomhlaba, kusukela olwandle olwandle kuya e-equator eshisayo, ubukhulu bube bubanzi kusuka ku-8 mm kuya ku-11 amamitha, futhi isisindo somuntu ngamunye sifinyelela ngaphezu kwamathani amabili. Igama, njengoba kunzima ukuqagela, lihlotshaniswa nesakhiwo sezinhlawulo ezihlanganisiwe, lapho kungekho khona i-basal axis. Iklasi, libuye lihlukaniswe ngamaqembu amabili: i-Novopyerye (izinhlobo eziphambili kakhulu) nezinhlanzi zaseKochchkryshchevye. Isakhiwo salo mkhakha sinezici ezihlukile. Banesisindo sokubhukuda, kodwa ngesikhathi esifanayo amasondo abo asemqoka ahlanganisa izicubu ze-cartilaginous. I-Chorda ine-arcs kuphela ye-cartilaginous futhi engaxhunywanga, imizimba ye-vertebral njengaleyo engekho. Isici esihlukile - i-rostrum nomlomo ophansi. Eziningi zazo zithengisa, ikakhulukazi i-sturgeon (esithombeni esingezansi - ukubanjwa kwe-beluga).

Inhlanzi ye-Lopastegre

Iklasi elincane lezinhlanzi, ama- skeleton alo esekelwe ekutheni ukhululekile. Zihlanganisa imikhuba eqhubekayo ne-archaic, bonke abameleli bangabalimi ababili banamuhla-Kystepery noDvojkoyyshyshye. Womabili amaqembu ahlanganisa inhlanzi yasendulo. Amaqhwa angamaqanda ahlala emzimbeni wamanzi ahlanzekile ase-Australia, eNingizimu Melika nase-Afrika. Abanayo amagill kuphela, kodwa namaphaphu. Lokhu kuvumela isikhathi esithile ukuba benze ngaphandle kwamanzi futhi bazizwe bekhululekile ukuchitha izikhumba zomoya. Ezingqikithi, izinhlobo ezingu-6 ziyaziwa: ama-four protopters ase-Afrika (isithombe ngezansi), ama-bastard ase-Australian naseNingizimu Melika.

Nadotryad Kistepery

Kucatshangwa ukuthi sekuphelile. Kuze kube manje, i-genus eyodwa kuphela ifikile - i-Latimiria (efanekiselwe ngezansi), enezinhlobo ezimbili. Futhi bobabili babetholakala kungekudala, isibonelo sokuqala sabanjwa e-Indian Ocean ngo-1938. Kukholelwa ukuthi izinhlanzi ze-cystepper yizakhamizi zamanzi amanzi amanzi lapho kwakungekho ukuntuleka kwe-oxygen. Kulokhu, bahlakulela ama-musculature phansi kwamafinini kanye nendlela yokuphefumula kabili (amaphaphu namagill). Lokhu kwavumela abanye ukuba babuyele emanzini, futhi amanzi ahlanzekile agcina esefa. Kukhona ukucabanga ukuthi kwakuyizinhlanzi ze-cystpie ezanikeza iklasi lama-Amphibians.

Ngakho-ke, izinhlanzi ezinamazinyo, izinhlanzi zethambo zinezici ezimbalwa. Okuyinhloko kubonakala ngesakhiwo se-skeleton (i-cartilaginous noma ibony), ukutholakala noma ukungabikho kwesigqila sokubhukuda, uhlobo lwezikali, uhlelo lokuzala kanye nendlela yokukhiqiza.