Uma imvelo inothe kunoma yini, ilingana ncamashi nenani elikhulu lezinto eziphilayo enazo. Inani elingapheli lezinhlobo zezilwane ligcwalisa ubude nobubanzi beplanethi yethu nezinhlelo zayo zemvelo ezihlukene. Uma sigxila ezinhlanzini, izinto bezingeke zibe ngaphansi. Kunezinhlobo eziningi de peces, okukhona neqembu elingajwayelekile: inhlanzi enesigaxa.
Ngokuqinisekile, kwabaningi le nhlanzi enesihlakala ingazwakala ingajwayelekile. Akukho okungaba kude neqiniso. Kulesi sihloko sizozama ukukusondeza kulolu hlobo lwesilwane nokuthi wazi okuningi ngazo.
Ziyini izinhlanzi ezinesigaxa?
Izinhlanzi ezigcwele imithambo yilezo ezibonakaliswa Unamathambo akhiwa uqwanga esikhundleni samathambo. Ngakho igama layo. Izidalwa ezinjengoshaka noma imisebe ezomndeni.
Ngaphezu kwalokho, lolu hlobo de peces Zibuye zibizwe njalo mxolisinhle, ngoba igama layo lesayensi ngu Skhokho.
Origen
Izinhlanzi ezinamathambo alinganiselwa ukuthi zizovela okokuqala eMhlabeni ngalesi sikhathi I-Upper Devonian. Lezi zinhlanzi kukholakala ukuthi zijabulele izikhathi ezimbili ezinkulu zokunwetshwa. Okokuqala kwalokhu kwakusekuqaleni I-Permian bese kuthi eyesibili, ibonakale kakhulu, ibheke maphakathi nendawo Okuhle kakhulu.
Izici ezivame kakhulu zezinhlanzi ezi-cartilaginous
Lezi zinhlanzi zinochungechunge lwezici ezikhethekile, ezibenza babe izidalwa ezithakazelisa ngempela.
Owokuqala wabo, futhi mhlawumbe oheha ukunakwa okukhulu, ukuthi bayethula inothi besebancane. Futhi ... yini inothi? Luhlobo lwezintambo izilwane zomndeni we-chordate ezinalo ngemuva futhi ezisebenza njengomgogodla. Le notochord izongena esikhundleni njengoba umuntu evuthwa, anikeze uqwanga lwangempela, okuzoba yilolo olwakha amathambo ngokuqinisekile.
Sijwayele ukubona ukuthi izinhlanzi zivamise ukuba nokubukeka okwehlukile okuzenza zibonakale zithambile ngasikhathi sinye. Yebo, ezinhlanzini ezibusayo kwenzeka okuphambene, ngoba lokhu zithambile emhlane noma esiswini. Esinye sezimbangela zalesi sici kungenzeka kungenxa yokushoda kwezimbambo noma isakhiwo esifanayo. Futhi ngenxa yalesi sizathu, uma lezi zinhlanzi zishiya i-ecosystem yasemanzini zingafa ngesikhathi esifushane kakhulu ngoba isisindo somzimba wazo sizobenza ukuthi "bawe", bachoboze futhi babhubhise izitho zabo zangaphakathi.
Imizimba yabo imbozwe esikalini esibizwa ama-dermal denticles. Lezi zikali zinomsebenzi ophindwe kabili: ukuvikela kanye ne-hydrodynamic. Uma sithinta inhlanzi enesigaxa singaqaphela ukuthi isikhumba sayo sithambile uma sitshelezisela isandla sethu kolunye uhlangothi, kepha ukuthi lesi simo siguqulwa ngokuphelele uma sikwenza ngendlela ehlukile. Isizathu salokhu sicacile: zonke lezi zikali ezincane zitholakala ngendlela efanayo nangendlela efanayo.
Njengoba kuvame ukwenzeka kuzo zonke izinhlanzi, ukuphefumula kulolu hlobo lwesilwane kwenzeka ngokusebenzisa izigaxa, ezingavikelekile nganoma yisiphi isitho esikhethekile, into evame ukwenzeka ezinhlanzini eziningi ezingamathambo.
Inkinga enkulu ethinta inhlanzi enesigaxa ukuthi awunaso isinye sokubhukuda (I-Organ ngesimo sesikhwama esine-membranous esitholakala ngaphansi komgogodla wenhlanzi, ogcwalisa igesi, okhuthaza ukwanda) Kwenzekani-ke? Yebo, baphoqeleka ukuba babhukude futhi bahlale bekhuthele ukuze bahlale betha.
Abanye babo banesitho esikhethekile esibizwa ngokuthi umugqa oseceleni, ewusizo olukhulu kubo ukuze bakwazi ukuthwebula ukudlidlizela. Inzwa yokuhogela ithuthukiswa kakhulu kulezi zinhlanzi, okuphambene nalokho okwenzekayo ngomqondo wokubona.
Ukudla
Asikwazi ukuthola izinhlanzi ezihlwabusayo endaweni ethile ochungechungeni lokudla. Kodwa-ke, iningi lalezi zilwane imvamisa liyizilwane ezidla inyama futhi futhi lingabazingeli abakhulu. Yize kukhona nalabo abathanda ukudla okususelwa ezitshalweni, eplankton, njll.
Ukuzala
Ukuzaliswa kwalolu hlobo lwesilwane kungohlobo ezocansi kanye ne-dioecious, okusho ukuthi sinabantu besilisa nabesifazane. Le nqubo yokuzala ibuye yehlukanise nezinhlanzi ezinamathambo, ngoba ukuvundiswa kwangaphakathi kwenzeka e-chondrichthyans. Isitho sokukopisha samadoda sibizwa izigaxa.
Inzalo yezinhlanzi ezisenkingeni ingaba izinhlobo ezintathu: i-oviparous, i-ovoviviparous ne-viviparous, kuya ngezinhlobo uqobo lwazo. Endabeni yezinhlanzi ezi-oviparous cartilaginous, amaqanda ngokuvamile makhulu.
Ngokuvamile abanenani eliphakeme lezinsizwa emjikelezweni ngamunye wokuzala, futhi ababona abazali abavikela kakhulu, ngaphandle kokunye okuhlukile.
Ukuhlukaniswa
Uma kukhulunywa ngokubhekisa ezinhlanzini ezibushelelezi, kufanele sazi ukuthi ngaphakathi kwalesi sigaba, singathola ama-subtypes amabili ahlukaniswe kahle. Ngakolunye uhlangothi sinefayela le- Ama-Slamiobranchs, ngakolunye Holocephalos. Ngokulandelayo, ngokwabo Ama-Slamiobranchs singahlukanisa phakathi kwe- Ama-Selacimorphs futhi i Ama-Bastoid.
AmaSelacimorphs yilokho esikwazi kakhulu njengoshaka noma oshaka. Zifana kakhulu nezinhlanzi ezinamathambo. Ama-Bastoid abhekisa ezilwaneni esizibiza ngokuthi ama-mantas, imisebe, imisebe kagesi, kanye ne-sawfish.
Ngokuqondene namaHolocephalos, futhi ngeshwa, kufanele kuqashelwe ukuthi iningi lawo selivele lingasekho. Njengamanje sithola kuphela iqembu elincane labo, elibizwa ngokuthi AmaChimera. Akungabazeki ukuthi, izinhlanzi ezithile ikakhulukazi, ikakhulukazi ngenxa yokubukeka kwazo ngokomzimba, lapho inhloko ivelele khona iphuma ngokweqile emzimbeni, ine-boa esesimweni senqwaba esesiswini.
Njengoshaka, ama-chimera nawo afana ngokufana nezinhlanzi ezinamathambo, kufaka phakathi ukubonakala kwe-operculum. Zivame ukuhlala ezansi kwezilwandle nezilwandle, lapho zidla khona izinhlanzi nezilwane ezincane ezingenamgogodla.
Ngiyethemba ukuthi ngale ndatshana ukwazile ukwazi kangcono izinhlanzi ezihlwabusayo, kanye namasiko abo, izici zabo, njll. Njengoba ubonile, akuzona izidalwa ezixakile futhi ngokuqinisekile ngaphezu kweyodwa umangele ukuzithola.