Thermoregulating Ectotherm

Daga Jake Zadik, tsohon kwararre a fannin sadarwa tare da The Ocean Foundation wanda yanzu ke karatu a Cuba.

Don haka, kuna tambaya, menene thermoregulating ectotherm? Kalmar “ectotherm” tana nufin dabbobin da gabaɗaya suna da zafin jiki kwatankwacin yanayin kewayensu. Ba za su iya daidaita zafin jikinsu a ciki ba. Sau da yawa mutane suna kiran su da "jini mai sanyi", amma wannan kalmar tana nuna karkatar da mutane sau da yawa fiye da a'a. Ectotherms sun haɗa da dabbobi masu rarrafe, masu amphibians, da kifi. Waɗannan dabbobin suna yin bunƙasa a wurare masu zafi. Dorewar samar da makamashi mai dumi-dumi (mammal) da dabba mai sanyi (mai rarrafe) a matsayin aikin zafin jiki.

"Thermoregulating," yana nufin ikon dabbobi don kula da zafin jiki na ciki, ba tare da la'akari da yanayin zafi ba. Lokacin sanyi a waje, waɗannan kwayoyin halitta suna da ikon zama dumi. Lokacin zafi a waje, waɗannan dabbobin suna da ikon kwantar da kansu kuma ba za su yi zafi ba. Waɗannan su ne "endotherms," ​​kamar tsuntsaye da dabbobi masu shayarwa. Endotherms suna da ikon kiyaye yanayin zafin jiki akai-akai kuma ana kiran su da homeotherms.

Don haka, a wannan lokacin za ku iya gane cewa taken wannan shafi a zahiri sabani ne—kwayoyin da ba za su iya daidaita yanayin zafin jikinta ba amma a zahiri tana da ikon daidaita yanayin zafin jikinta? Haka ne, kuma hakika halitta ce ta musamman.

Wannan wata ne na kunkuru na teku a The Ocean Foundation, shi ya sa na zaɓi yin rubutu game da kunkuru na teku da kuma yanayin zafi na musamman. Binciken bin diddigin ya nuna wannan kunkuru yana da hanyoyin ƙaura a cikin tekuna, kuma ya kasance maziyartan maziyartan wurare da dama. Suna ƙaura zuwa wadataccen abinci mai gina jiki, amma ruwan sanyi sosai har zuwa arewacin Nova Scotia, Kanada, kuma suna da wuraren zama a cikin ruwan zafi a ko'ina cikin Caribbean. Babu wani dabba mai rarrafe da ke jure irin wannan yanayin yanayin zafi mai faɗi-na faɗa da ƙarfi saboda akwai dabbobi masu rarrafe waɗanda ke jurewa ƙasa da yanayin sanyi, amma yin haka a cikin yanayin sanyi. Wannan ya burge masana ilmin hanta da kuma masu nazarin halittun ruwa na tsawon shekaru da yawa, amma an gano kwanan nan cewa waɗannan manya-manyan dabbobi masu rarrafe suna daidaita yanayin yanayinsu.

Amma su ectotherms ne, ta yaya suke yin haka?…

Duk da girman girmansu da ƙaramar mota, ba su da ginanniyar tsarin dumama wanda ya zo daidai. Duk da haka girman su yana taka muhimmiyar rawa wajen daidaita yanayin yanayin su. Saboda suna da girma sosai, kunkuru na teku na leatherback suna da ƙananan yanki zuwa girman rabo, don haka ainihin zafin jiki na kunkuru yana canzawa a hankali sosai. Ana kiran wannan sabon abu "gigantothermy." Masana kimiyya da yawa sun yi imanin cewa wannan shi ma sifa ce ta manyan dabbobin da suka rigaya sun kasance a lokacin ƙarshen zamanin ƙanƙara kuma hakan ya kai ga bacewarsu yayin da yanayin zafi ya fara tashi (saboda sun kasa yin sanyi da sauri).

Har ila yau, kunkuru an naɗe shi a cikin wani nau'in adipose mai launin ruwan kasa mai launin ruwan kasa, wani kitse mai ƙarfi wanda aka fi samu a cikin dabbobi masu shayarwa. Wannan tsarin yana da ikon riƙe fiye da 90% na zafi a tsakiyar dabba, yana rage asarar zafi ta hanyar da aka fallasa. Lokacin a cikin ruwan zafi mai zafi, kawai akasin haka yana faruwa. Mitar bugun jini na jujjuyawa yana raguwa sosai, kuma jini yana motsawa da yardar kaina zuwa gaba kuma yana fitar da zafi ta wuraren da ba a rufe a cikin nama mai rufewa.

Kunkuru na teku na fata suna da nasara sosai wajen daidaita yanayin zafin jikinsu har suna da ikon kiyaye yawan zafin jiki na sama da digiri 18 sama ko ƙasa da yanayin yanayi. Wannan abin ban mamaki ne cewa wasu masu bincike suna jayayya saboda wannan tsari yana cika cikar kunkuru na teku na fata a zahiri endothermic. Duk da haka, wannan tsari ba a gudanar da shi ta hanyar jiki, saboda haka yawancin masu bincike suna ba da shawarar cewa wannan ƙananan sigar endothermy ne mafi kyau.

Kunkuru na fata ba shine kawai ectotherms na ruwa don mallakar wannan ikon ba. Bluefin tuna suna da tsarin jiki na musamman wanda ke kiyaye jininsu a tsakiyar jikinsu kuma suna da irin wannan tsarin musayar zafi na yanzu zuwa fata. Kifi na Swordfish yana riƙe zafi a kawunansu ta hanyar nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i) don haɓaka hangen nesa lokacin yin iyo a cikin ruwa mai zurfi ko sanyi. Akwai kuma wasu ƙattai na teku waɗanda ke rasa zafi a hankali a hankali, kamar babban kifin kifi.

Ina tsammanin thermoregulation ɗaya ne kawai mai ban sha'awa mai ban sha'awa na waɗannan kyawawan halittu masu kyan gani fiye da yadda ake saduwa da ido. Tun daga ƴan ƙanƙaran ƙyanƙyasar da ke kan hanyar zuwa ruwa zuwa ga mazaje masu tasowa da matan gida masu dawowa, har yanzu ba a san yawancin su ba. Masu bincike ba su da tabbacin inda waɗannan kunkuru suke ciyar da 'yan shekarun farko na rayuwarsu. Ya kasance wani abu mai ban mamaki kan yadda waɗannan manyan dabbobin da ke tafiya mai nisa ke tafiya da irin wannan daidai. Abin baƙin cikin shine muna koyo game da kunkuru na teku akan ƙimar da ta yi ƙasa sosai fiye da adadin raguwar yawansu.

A ƙarshe zai zama ƙudirinmu don kare abin da muka sani, da kuma sha'awarmu game da kunkuru na teku waɗanda ke haifar da ƙoƙarce-ƙoƙarce na kiyayewa. Akwai abubuwa da yawa da ba a sani ba game da waɗannan dabbobi masu ban sha'awa kuma rayuwar su na fuskantar barazanar asarar rairayin bakin teku, robobi da sauran gurɓataccen ruwa a cikin teku, da kamun kamun kifi da layin dogon. Taimaka mana a The Ocean Foundation tallafa wa waɗanda suka sadaukar da kansu ga binciken kunkuru na teku da ƙoƙarin kiyayewa ta hanyar Asusun Kunkuru na Teku.

References:

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