Rangarira ndima iri pasi apa uye ipapo pindura mubvunzo gare gare mumutauro mumwe chetewo sechikamu:  Kupfuura: Mazino e"shark" akawanikwa mumatombo anozivikanwa kubvira munguva yokutanga yeDevonian, makore anenge mamiriyoni 400 akapfuura. Munguva yakatevera yeCarboniferous, shark dzakapfuura nenguva yekusiyana-siyana, nemhando dzakawanda itsva dzichichinja. Vakawanda vavo vakatsakatika munguva yePermian, asi shark dzakanga dzasara dzakasangana nechiitiko chechipiri chokupararira kwemwaranzi panguva yeJurassic, panguva iyo makara nemasvosve zvakatanga kuoneka. Zvizhinji zvezvisikwa zvinoti Elasmobranch zvakapukunyuka zvakatanga munguva yeCretaceous, kana kuti yapfuura.  Mubvunzo: vanhu vakatsakatika rini
munguva yePermian