 Ramba uchinyora ndima iyi - Kwakatangira rudzi urwu inyaya yekukakavadzana kukuru sezvo zvimwe zvezvisaririra zvekutanga zvichiitika panguva yeIrvingtonian muFlorida neEnsenadan muUruguay. Pasinei neizvi, pane kubvumirana pakati pevanoongorora nezvezvinhu zvekare nezvekupararira kwePalaeolama panguva yeGreat American Biotic Interchange. Panewo uchapupu hunoratidza kutamira kuchamhembe kweSouth America panguva yechipiri yezviitiko zviviri zvekufamba kwePleistocene Camilidae. Uchapupu hwezvakacherwa hunotangira kumaodzanyemba kweNorth America kusanganisira California, Florida, neMexico kumaodzanyemba kuburikidza neCentral America uye hunoguma muSouth America Argentina neUruguay. 