Shuke-shuke masu cin nama Sun shahara sosai saboda babban halayen su: suna cin nama. Su shuke-shuke ne da kusan kowa ke son ganin wani lokaci a rayuwarsu, tunda ba al'ada bane tsiro yaci wani abu banda ruwa.
Amma tabbas, a wani lokaci, juyin halitta da ci gaban halittu masu rai an halicce su wannan yana buƙatar cin nama. Ta yaya shuke-shuke masu cin nama suka sami ɗanɗanar nama?
Jirgin dwarf
Jirgin dwarf tsire-tsire ne mai cin nama. Yana girma a Kudancin Ostiraliya. Wannan inji yana da wata hanya ta musamman ta ciyarwa. Godiya ga ƙamshi mai daɗin ƙanshi, yana jawo kwari. Da zarar kwaron ya sauka a kansa, sai ya yi amfani da irin kayan ganyen ganye don tarko su. Thewarin na ƙoƙarin tserewa sau da yawa, amma damar su ta ragu tunda, ƙari, ƙwayoyin enzymes na narkewa abinci na shuka vhar yanzu bazuwar dabba da raunana ta. Wadannan enzymes masu narkewar abinci suna canza dabba zuwa cikin abubuwan gina jiki masu mahimmanci wanda tsiron yake buƙatar ciyar da kansa.
Wannan hanyar ciyarwar tana da ban sha'awa sosai kuma ya bambanta da sauran shuke-shuke. Amma a wane lokaci ne suka haɓaka dandano na nama? Akwai karatuttuwa sakamakon tsarin jigidar halittar ta wanda zai bamu damar gano yadda wannan da wasu nau'ikan shuke-shuke masu cin nama sun haɓaka dandano na nama.
Jirgin dwarf yana da sunansa na kimiyya da aka sani da Cephalotus follicularis kuma da alama cewa Charles Darwin bai gano hakan ba a cikin balaguron sa. Darwin yayi tafiya zuwa yanki guda na Ostiraliya inda wannan tsiron yake girma, amma bai ganshi ba, tunda, a cikin aikinsa na tsire-tsire na kwari, bai ambaci wannan nau'in ba. Wannan ba yana nufin cewa Darwin bai hadu da shuke-shuke masu cin nama ba. A zahiri, yana bayyana wasu tsire-tsire masu yawa tare da wannan halayyar ta musamman.
Na gina jiki da ake buƙata don waɗannan tsire-tsire
A wancan lokacin, Darwin ya rigaya ya danganta wannan ɗanɗano mai ban mamaki da keɓance na waɗannan kayan lambu ga dabarun tsira a cikin mahalli maƙiya. Ya kuma zo ne ya sanar da gaskiyar cewa wadannan tsire-tsire suna samun karin abinci mai gina jiki kuma mafi yawa daga naman dabbobi maimakon daga ƙasa ta tushensu.
Dole ne mu tuna cewa waɗannan tsire-tsire, duk da ciyar da nama, suna iya yin hakan ta hanyar gargajiya. Shuke-shuke masu rarrafe a nahiyoyi uku sunyi tafiya akan tafarkin juyin halitta. Mahimman abubuwan gina jiki da suke buƙata don rayuwa da abin da suka samu musamman sune nitrogen da phosphorus. Wannan ita ce martanin da shuke-shuke na yau da kullun daga ƙasa mai talauci suke da shi. Watau, waɗannan tsire-tsire waɗanda ke mai da hankali kan shan nitrogen da phosphorus galibi, suna rayuwa ne a ƙarancin nitrogen da ƙasa mara kyau.
Tsire-tsire yana da ƙwarewa cewa yayin da wani ɓangare na ganyayyakinsa lebur suke kuma suna da aikin gargajiyar gargajiyar hoto, wasu ana tsara su don yin butar da ke jan hankali, tarko, narkewa da tsotse kwari. Wannan biyun ya sanya ya yiwu a kwatanta bayyanar kwayoyin halitta a cikin wasu ganyayyaki da kuma wasu.
Yadda suka sami ɗanɗano na nama
An gudanar da bincike daban-daban don bayyana wannan gaskiyar. An samo shi a cikin binciken da aka buga a Yanayin Ilimin Halitta & Juyin Halitta Dalilin haka. Da alama wasu rukunin sunadarai wadanda tun farko suka tsoma baki a cikin tsarin kariya na dwarf jug a kan kwayoyin cuta ko kuma magance damuwar shuke-shuke, yanzu an sadaukar dasu don samar da enzymes masu narkewa.
Daya daga cikin ainihin enzymes da ke aiki a cikin wannan nau'in aikin narkewar abinci shine chitinase. Wannan enzyme ne ke da alhakin lalata chitin na exoskeleton na kwari. Wani enzyme wanda ke taimaka muku assimilate phosphorus wanda ke sace wadanda kuke fama shine phosphatase. Kamar yadda na ambata a baya, wannan yanayin martani ne na waɗannan tsire-tsire waɗanda ke iya rayuwa a cikin ƙasa mai talauci. Bayan lokaci, waɗannan tsire-tsire sun kirkiro wata hanya don samun nitrogen da phosphorus daga kwari, tunda a cikin ƙasa mara kyau ba za su iya rayuwa da kyau ba.