Amayobera y’udusimba two mu nyanja duhindura icyerekezo cy’ibikonoshwa

Abashakashatsi bavumbuye ikintu kidasanzwe mu bisigazwa by’utunyabuzima duto two mu nyanja bizwi nka foraminifera : rimwe na rimwe bihindura icyerekezo ibikonoshwa byabyo bizengurukamo, kandi impinduka nk’izi zikagaragara mu nyanja zitandukanye ku Isi. Foraminifera ni utunyabuzima tugizwe n’akaremangingo kamwe, tuboneka mu nyanja hafi ya hose. Twubaka ibikonoshwa bikomeye birimo utwobo twinshi. Iyo dupfuye, ibyo bikonoshwa birundana hasi mu nyanja, bikaba ububiko kamere bufasha abahanga kwiga amateka y’ikirere n’inyanja mu myaka miriyoni. Icyatangaje abashakashatsi ni uko muri bumwe muri ubu

Abashakashatsi bavumbuye ikintu kidasanzwe mu bisigazwa by’utunyabuzima duto two mu nyanja bizwi nka foraminifera: rimwe na rimwe bihindura icyerekezo ibikonoshwa byabyo bizengurukamo, kandi impinduka nk’izi zikagaragara mu nyanja zitandukanye ku Isi. Foraminifera ni utunyabuzima tugizwe n’akaremangingo kamwe, tuboneka mu nyanja hafi ya hose. Twubaka ibikonoshwa bikomeye birimo utwobo twinshi. Iyo dupfuye, ibyo bikonoshwa birundana hasi mu nyanja, bikaba ububiko kamere bufasha abahanga kwiga amateka y’ikirere n’inyanja mu myaka miriyoni. Icyatangaje abashakashatsi ni uko muri bumwe muri ubu bwoko, hafi 97% y’ibinyabuzima bishobora kuba bizenguruka igikonoshwa mu cyerekezo kimwe. Ariko nyuma y’imyaka ibihumbi cyangwa miriyoni, icyerekezo cyiganje gishobora guhinduka. Mu myaka ya za 1950, abahanga batekereje ko ubushyuhe bw’inyanja bushobora kuba ari bwo butera izi mpinduka. Ubushakashatsi bwakurikiyeho ariko bwagaragaje ko guhinduka kw’icyerekezo bitajyana buri gihe n’imihindagurikire y’ubushyuhe. Itsinda ry’abashakashatsi bo muri University College London ryasesenguye amakuru yakusanyijwe mu bushakashatsi bwamaze imyaka myinshi, harebwa foraminifera zabayeho mu myaka igera kuri miliyoni 56 ishize. Basanze hari ubwoko bwahinduraga icyerekezo mu nyanja zitandukanye ndetse no mu turere dufite ikirere gitandukanye. Abashakashatsi bakeka ko iri hinduka rishobora kuba ridaturuka ku gikonoshwa ubwacyo, ahubwo rikaba ikimenyetso cy’impinduka ikomeye mu bwoko bw’ibinyabuzima. Itsinda rito rifite akarusho mu kubaho cyangwa kororoka rishobora kuba ryaratangiriye ahantu hamwe, nyuma rigakwira mu nyanja nyinshi, kugeza rihinduye igipimo cy’ibinyabuzima byari bisanzweho. Nubwo iyi nyigisho itanga ibisobanuro bishya, impamvu nyayo ituma ubu bwoko bumwe bukunda kuzenguruka iburyo cyangwa ibumoso iracyari amayobera. Abahanga bavuga ko ibi bishobora kuba ari uburyo budasanzwe bwo kureba uko ihindagurika ry’ibinyabuzima rishobora gutangirira ku itsinda rito, rigakwira ku rugero rw’Isi yose. Igitangaje ni uko igikonoshwa kiri munsi ya milimetero imwe gishobora kuba kibitse amateka y’impinduka nini zabaye mu binyabuzima byo ku Isi.