Answer: The Cenozoic era.
Explanation: The Cenozoic era started started over 65.5 million years ago till present.
This era is divided into 3 periods : Paleogene, Neogene and Quaternary. This era started after the extinction of the dinosaur. Mammals were dominant in this era.
Previously dinosaurs were dominant and ruled over the whole earth but after a meteorite activity dinosaurs got extinct and mammals ruled over the planet.
