I-Kiel i ... Kutheni iintaka zifuna

Izilwanyana kunye neentaka yi-vertex ye-vertebrate evolution. Bobabini babonakala ngexesha elifanayo. Ngona kwixesha le-Triassic, kubakho izilwanyana zokuqala ezibonakalayo, ezahlukana nezilonda. Babeneminyaka yokuqala kwaye babengabonakali njengezilwanyana zanamhlanje. Kwaye ekuqaleni kwexesha leJurassic, ukusuka kwiilzards zomhlaba, abantu abahamba ngeenqanawa zenzeke, eziye zavelisa iklasi yeentaka.

Izilwanyana ezingapheliyo zihlala kuyo yonke indawo, ezavumela iintaka zokuqala kunye nezilwanyana ukuba zihlale kwiindawo ezingasimahla. Yaye inyaniso yokuba banqoba amazwe amasha awazange asetyenziswe ngaphambili ngama-lizards, yabangela ukuba izilwanyana kunye neentaka zibonakala zivumelane nokuphila kwiimeko ezahlukeneyo. Izilwanyana zintlintliso eziphambili, ngenxa yazo iintaka zivelise inkqubo ye-nervous, izitho zengqondo kunye nokuziphatha. Namhlanje sinomdla kakhulu kumbuzo wesakhiwo. Sincoma ukuba siqhelane nelo nxalenye yomzimba njenge-keel. Oku kulungelelanisa kwiintaka nezinye izilwanyana. Yintoni, yintoni imisebenzi eyenziwa, sifunda kulo msebenzi.

Ulwakhiwo lweentaka

Iintaka ezininzi zingakwazi ukundiza, ezinye iimeko zokuziphendukela kwemvelo ziye zalahleka lo mkhono. Ngoku makhe sithethe encinci malunga nesakhiwo sezi zidalwa ezikhanyayo nezomoya. Amathambo amathumbu azaliswe ngetyuwa yokubala avumela iintaka ukuba zibale, ngoko i-skeleton yazo iba yomelele kwaye ilula. Intaka ihluke kakhulu kwiintaka: eludongeni olungaphambili zikhona iziseko ezinkulu zamehlo kunye nenkuni, eyayibe ngumhlathi emanzini.

Intamo ihluke ngobude kunye nokuhamba, ine-vertebrae elishumi ukuya kumashumi amabini anesihlanu. Ekubeni iimbambano ziyi maphiko, umthwalo kwimilenze uye wanda: amathambo ayenze inxalenye ye-pelvic sele yanda kunye, ngoko yomelela. Kukho iinkalo kwisakhiwo se-humerus, umzekelo-keel. Lona ithambo elinamandla kakhulu, likhonza njengentaba yezihlunu zepectoral. Makhe sithethe ngale nto encinane.

Kiel

Njengoko sithe satshilo, i-keel yinto ephakamileyo efunekayo kwiintaka ukukhawuleza izihlunu zepectoral. Olu phuhliso lwakhiwa kwinkqubo yokuziphendukela kwemvelo, kuba iintaka zingakwazi ukundibonga ngenxa yale fowuni, kuba imisipha ye-pectoral iphuhliswe kakhulu. Akunjalo kuphela kwiintaka, kodwa nakwezinye izilwanyana ezineempembelelo ezinamandla: njengomthetho, zimba umhlaba. Umzekelo unokusebenza njenge-mole. Kodwa i-keel inokuphuhliswa okhethekileyo kwiintaka ezindizayo, iilwane. Kukho iintlobo zeentaka ze- keel : i-hummingbirds, i- swifts njalonjalo. Oko kukuthi, sinokuthi i-keel isixhobo seentaka kunye nokumba izilwanyana, ngaphandle kokungenakukwazi ukwenza ngaphandle kwazo.

Imisebenzi

Ingqungquthela kukuba, kwiintaka, ngokukodwa ukukhula kwethambo kummandla we-thoracic, ithambileyo, isebenza ukudibanisa izihlunu ezinamandla ezibandakanyekayo ekuhambeni. Masigxininise injongo kunye nemisebenzi yale nkqubo yethambo.

• I-keel iyadingeka ukuze kuqiniswe isebe le-thoracic, oko kukuthi, isifuba kule nxalenye sinamandla. Singaxelela ukuba sisixhobo esongezelelweyo sokukhusela izitho ezibalulekileyo.
• Ekubeni iintaka zinemisipha eninzi ngexesha lokunyuka kwamaphiko, i-keel yinto efana neenombolo zee-fibre muscle.
• Kwakhona, oku kuphakanyiswa kukukhuthaza ukuhamba kwendawo yomzimba. Oku kukuvumela ukuba wenze ukunyakaza okujonge xa uphefumula.
• Umsebenzi wokugqibela utshintsho kwindlela yokuhamba, i-keel ihlala kude kwindawo yokugqibela kule nkqubo.

Ziziphi iintaka ezingenayo i-keel

Ngoko, keel - yintoni na? Siphendule lo mbuzo. Kwathethwa ukuba kukho iintlobo zeentaka, kodwa abazange bathethe ngokungafani. Kubalulekile ukucacisa ukuba kukho i-subclass yama-ratites. Ngaphambili babizwa ngokuba njalo:

• Ukuqalisa.
• I nciniba.
• I-Smooth-chested.

Eli klasi liquka amanqaku angama-8:

• Casuaro-like.
• Kiwifruit.
• E-Nandoo.
• Nengqiqo.
• Tynamuiformes.
• Epiornosposobnye.
• Efana neLiturnite.
• Omoya.

Ngeentlanganiso ezintathu zokugqibela, abaninzi abanakuze beve nonke, kuba ababameli babo bebede befile.