The Cenozoic is an era in Earth's history. We are in the Cenozoic. It featured the rise of mammals after the demise of the dinosaurs. The Cenozoic Era is highly significant for us humans - as we would not even be here if it were not for the titanic climate changes and good fortune (not to mention the convenient 'removal' of the dinosaurs) the mammals were granted right from the start of this era. It is a time of changes, and two major extinction events took place during this Period: the Eocene-Oligocene Extinction Event, which wiped out 1 in 5 living organisms, and the Pleistocene-Holocene Extinction, which has been triggered by humanity and is, in the long run, second only to the Great Permian Mass Extinction Event in its damage to the global ecosystems.


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