Thermoregulating Ectotherm

Wolemba Jake Zadik, yemwe kale anali mlangizi wolumikizana ndi The Ocean Foundation yemwe tsopano akuphunzira ku Cuba.

Ndiye mukufunsa, kodi ectotherm ya thermoregulating ndi chiyani? Mawu akuti "ectotherm" amatanthauza nyama zomwe nthawi zambiri zimakhala ndi kutentha kwa thupi mofanana ndi malo ozungulira. Sangathe kuwongolera kutentha kwa thupi lawo mkati. Anthu nthawi zambiri amawatchula kuti "ozizira", koma mawuwa amakonda kusokeretsa anthu nthawi zambiri. Ectotherms amaphatikizapo zokwawa, amphibians, ndi nsomba. Nyama zimenezi zimakonda kukhala bwino m’malo otentha. Mphamvu zokhazikika zamagazi ofunda (nyama yoyamwitsa) ndi nyama yozizira (yokwawa) ngati ntchito ya kutentha kwapakati.

“Thermoregulating,” amatanthauza kukhoza kwa nyama kusunga kutentha kwa mkati mwawo, mosasamala kanthu za kutentha. Kunja kukazizira, zamoyo zimenezi zimatha kutentha. Kunja kukatentha, nyamazi zimatha kudziziziritsa osati kutentha kwambiri. Ameneŵa ndiwo “endotherm,” monga mbalame ndi nyama zoyamwitsa. Endotherms amatha kusunga kutentha kwa thupi nthawi zonse ndipo amatchedwanso homeotherms.

Ndiye, panthawiyi mutha kuzindikira kuti mutu wabulogu iyi ndi wotsutsana-chamoyo chomwe sichingathe kuwongolera kutentha kwa thupi koma chimakhala ndi mphamvu zowongolera kutentha kwa thupi lake? Inde, ndipo ndi cholengedwa chapadera kwambiri.

Uno ndi mwezi wa kamba wa kunyanja ku The Ocean Foundation, ndichifukwa chake ndasankha kulemba za kamba wam'nyanja wa leatherback ndi kutenthetsa kwake kwapadera. Kafukufuku wotsatira awonetsa kuti kambayu ali ndi njira zosamuka kudutsa nyanja zamchere, komanso kukhala oyendera malo osiyanasiyana. Amasamukira kumadzi olemera, koma ozizira kwambiri kumpoto monga Nova Scotia, Canada, ndipo amakhala ndi malo odyetserako zisa m'madzi otentha ku Caribbean. Palibe chokwawa china chomwe chimalekerera kutentha kosiyanasiyana koteroko-ndikunena mwachangu chifukwa pali zokwawa zomwe zimalekerera kuzizira kozizira, koma zimatero mu hibernating state. Zimenezi zachititsa chidwi akatswiri a zamoyo ndi zamoyo zam’madzi kwa zaka zambiri, koma posachedwapa atulukira kuti zokwawa zazikuluzikuluzi zimayendetsa bwino kutentha kwawo.

…Koma ndi ma ectotherm, amachita bwanji izi?…

Ngakhale akufanana kukula ndi galimoto yaying'ono yaying'ono, alibe makina otenthetsera omwe amabwera muyezo. Komabe kukula kwawo kumachita gawo lalikulu pakuwongolera kutentha kwawo. Chifukwa chakuti ndi aakulu kwambiri, akamba am’madzi a m’nyanja a leatherback amakhala ndi malo otsika kwambiri moti amasinthasintha kutentha kwapakati pa kamba. Chodabwitsa ichi chimatchedwa "gigantothermy". Asayansi ambiri amakhulupirira kuti ichi chinalinso chikhalidwe cha nyama zazikulu zambiri zakale zomwe zidachitika pachimake cha nyengo ya ayezi ndipo pamapeto pake zidapangitsa kuti ziwonongeke pamene kutentha kunayamba kukwera (chifukwa sakanatha kuzizira mokwanira).

Kambayo amakulungidwanso mu minofu ya bulauni ya adipose, mafuta oteteza kwambiri omwe amapezeka kwambiri mwa nyama zoyamwitsa. Dongosololi limatha kusunga kutentha kopitilira 90% pakatikati pa nyama, kumachepetsa kutayika kwa kutentha kudzera m'malo owonekera. M'madzi otentha kwambiri, zosiyana zimachitika. Flipper sitiroko pafupipafupi amachepetsa kwambiri, ndipo magazi amayenda momasuka ku malekezero ndi kutulutsa kutentha kupyola madera osaphimbidwa mu insulating minofu.

Akamba am'nyanja a Leatherback amakwanitsa kuwongolera kutentha kwa thupi lawo kotero kuti amatha kusunga kutentha kwa thupi mpaka madigiri 18 pamwamba kapena pansi pa kutentha kozungulira. Izi ndizodabwitsa kwambiri kotero kuti ofufuza ena amatsutsa chifukwa njirayi imakwaniritsidwa bwino ndi akamba am'madzi am'madzi omwe amakhala ndi moyo. Komabe, izi sizimachitidwa mwachilengedwe, chifukwa chake ofufuza ambiri akuwonetsa kuti iyi ndi mtundu wocheperako wa endothermy.

Akamba a Leatherback si ma ectotherms am'madzi okha omwe ali ndi luso limeneli. Bluefin tuna ili ndi mawonekedwe apadera a thupi omwe amasunga magazi awo pachimake cha thupi lawo ndipo amakhala ndi makina ofananira nawo apano a kutentha kwa leatherback. Swordfish imasunga kutentha pamutu pawo kudzera m'mizere yofananira ya bulauni ya adipose kuti iwonjezere kuwona kwawo ikasambira m'madzi akuya kapena ozizira. Palinso zimphona zina za m’nyanja zomwe zimataya kutentha pang’onopang’ono, monga shaki yaikulu yoyera.

Ndikuganiza kuti thermoregulation ndi chimodzi mwazinthu zochititsa chidwi kwambiri za zolengedwa zazikuluzikuluzi zomwe zili ndi zambiri kuposa momwe zimawonekera. Kuyambira ana aang’ono amene amaswa zisa zawo kupita kumadzi mpaka kukafika ku anyani aamuna osatha ndinso aakazi obwerera kwawo, zambiri zokhudza iwo sizikudziwikabe. Ofufuza sakudziwa kumene akamba amenewa amakhala zaka zingapo zoyambirira za moyo wawo. N’zosadabwitsa kuti nyama zoyenda mtunda wautalizi zimayendera bwino kwambiri. Tsoka ilo tikuphunzira za akamba am'nyanja pamlingo wocheperapo kuposa momwe kuchuluka kwawo kukucheperachepera.

Pamapeto pake kuyenera kukhala kutsimikiza mtima kwathu kuteteza zomwe tikudziwa, komanso chidwi chathu chokhudza akamba am'nyanja odabwitsa omwe amatsogolera ku kuyesetsa mwamphamvu kuteteza. Pali zambiri zosadziŵika ponena za nyama zochititsa chidwizi ndipo moyo wawo uli pangozi chifukwa cha kutayika kwa magombe osungira zisa, mapulasitiki ndi kuipitsa kwina kwa nyanja, ndi kugwidwa mwangozi muukonde wophera nsomba ndi mizere yaitali. Tithandizeni pa The Ocean Foundation thandizirani omwe adzipereka pantchito zofufuza za kamba za m'nyanja ndi ntchito zosamalira zachilengedwe kudzera mu Fund yathu ya Turtle Fund.

Zothandizira:

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