The geologic time scale is divided into eons, eras, periods, epochs, and ages. Our activities ... other animal groups 65.5 million years ago defines the beginning of the Cenozoic era. We are including ...

3 min read At the dawn of the Paleogene—the beginning of the Cenozoic era—dinosaurs, pterosaurs, and giant marine reptiles were conspicuously absent from the face of the Earth. Rodent-size ...

Figure 1: Summary of orbital timescale calibrations for the Cenozoic era in the context of climatic ... to be accomplished in the middle Eocene epoch (∼40 to 50 million years).

The Early Cretaceous Epoch lasted from 145 million years ago to 100.5 million ... When the Cretaceous Period and Mesozoic Era ended 66 million years ago, the Palaeogene Period and the Cenozoic Era ...