Zamanin dinosaur, ammonites suma sun kasance sun bace miliyoyin shekaru da suka gabata. Sun zauna a yankuna daban-daban na ruwa kuma har yanzu ana iya samun sawun sawunsu a wurare daban-daban a duniya.
Zamanin dinosaur, ammonites suma sun kasance sun bace miliyoyin shekaru da suka gabata. Sun zauna a yankuna daban-daban na ruwa kuma har yanzu ana iya samun sawun sawunsu a wurare daban-daban a duniya.
Waɗannan cephalopods tare da kwasfa na waje suna da saurin juyin halitta da gajere. Sun rayu daga Devonian, a zamanin Paleozoic, zuwa Mesozoic. Godiya ga yanayin sassaucin halittar su, sun sami damar saba da yanayin rayuwa daban-daban: iri daya a cikin zurfin teku kamar yadda yake a cikin bude teku da kuma yankunan da ke kewaye da nahiyoyin duniya.
A halin yanzu, ana samun dangin su mafi kusa a cikin kwayoyin kamar Argonauts da Nautilus, amma ba kamar na farko ba, ba su da yawan kasancewar duniya.
Daya daga cikin halittun da masana burbushin halittu suka fi sani shine ammonites daidai. Ga masu bincike suna aiki azaman kyakkyawan alama na lokaci, saboda haka ana kiransu da Rólexes of paleontology. Hakanan, saboda yana yiwuwa a sami burbushinsu a warwatse ko'ina cikin duniya, sune matattakan duniya game da siffofin rayuwa da suka ɓace. Ari ga haka, kasancewar sa a bayyane yana taimaka wa masana kimiyya su daidaita tsakanin abubuwa daban-daban a duniya.
Idan a rayuwar ɗan adam shekaru miliyan suna da shekaru masu yawa, a lokacin ilimin ƙasa ya yi daidai da ɗan gajeren lokaci. Waɗannan canje-canjen da aka samu daga mataki ɗaya zuwa wani alamu ne na ban mamaki don ƙayyade shekarun duwatsu, tunda waɗannan ana iya rarraba su daga bayanan da ammonites suka bari, waɗanda burbushinsu yake tare da abubuwa masu alaƙa waɗanda ke nuna takamaiman yanayin rayuwa.
Masana burbushin halittu ba su bayar da hakikanin adadin shekarun ba, amma daga karatunsu yana yiwuwa a san halittun da suka fara rayuwa, wadanne daga baya kuma zuwa wane mataki da yanayin da suka dace.
Godiya ga tarin duwatsu masu tarin yawa a Mexico, akwai burbushin wadannan halittu wadanda suka fara daga miliyan 320 zuwa shekaru miliyan 65. Karatunta a cikin kasarmu an yi su ne cikin gaggawa. Nazarin binciken farko wanda ya samo asali na kimiyya game da ammonites a Mexico ana bin bashin mai binciken Switzerland Carl Burckhardt. Ayyukan baya-baya na wasu Jamusawa, Amurkawa da Faransawa sun biyo baya.
A karni na ashirin, binciken masana kimiyya daban-daban ya ba da sabuwar kwarin gwiwa ga wannan aiki, tun da yake babban yankin Mexico har yanzu yana dauke da enigmas da yawa, saboda haka har yanzu masana suna da yawa da za su bincika: akwai duwatsun da ke cikin teku a cikin kasar Sierra Madre Oriental , a cikin Baja California da Huasteca, a tsakanin sauran wurare.
Don gano ammonites, koyaushe muna farawa daga karatun da suka gabata, ba wai kawai burbushin halittu ba, amma ilimin ƙasa gaba ɗaya. Tare da taswirar ƙasa a hannu, rukunin masu binciken sun tashi zuwa filin. Ana iya amfani da wannan taswirar don a sami kusancin farko da shekarun duwatsu.
Tuni a ƙasa an zaɓi saitin duwatsu, daga inda ake ɗaukar samfurin. Bayan murkushe dutsen, an samo burbushin halittu; Amma ba wai batun raba duwatsu ba ne kawai, cire ammonite da rashin kula da sauran, tunda a cikin wadannan tambayoyin zamu iya samun ragowar shuke-shuke ko masu jujjuya halitta wadanda ke bayyana wasu alamomi na yanayin sararin samaniya wadanda dole ne a warware su don samun bayani mai ban mamaki.
A saboda wannan dalili, gabaɗaya, ƙungiyoyin binciken sun kasance daga ƙungiyar ƙwararrun masana masu yawa. Ta wannan hanyar, kowane gwani yana ba da gudummawar iliminsa don bayyana abubuwan da suka shafi kowane bincike.
A fagen, masana kimiyya suna samun amsoshi saboda wurin da burbushin yake, amma kuma gaskiya ne cewa idan babu su, hakan ma ya zama bayanai, sannan kalubalen shine sanin dalilin da yasa babu burbushin halittar a wurin.
Ba wai duwatsun basa magana bane, amma sun yi shuru ne na shekaru miliyoyi. Tambaya ta gama gari tsakanin mutane ita ce: "Mecece wancan?" Daga nan sai masu bincike suka zama masu yadawa ta hanyar bayanin mahimmancin fahimtar asali da canjin rayuwa.
Saboda launi da fasalin su, ammonites suna jan hankalin ido. Duk da cewa doka tana kiyaye kayan tarihi, a wasu kasuwannin ana sayar da kasusuwan tarihi a matsayin kayan adon kuma ba a la'akari da cewa wannan kasuwancin yana haifar da asarar ƙididdigar kimiyya mai mahimmanci.
Source: Ba a san Mexico ba No. 341 / Yuli 2005
