What occurred during the Cenozoic era?
c. dinosaur extinction
The Cenozoic Era, which began about 65 million years ago and continues into the present, is the third documented era in the history of Earth.
The era began on a big down note, catching the tail end of the Cretaceous-Paleogene extinction event at the close of the Cretaceous Period that wiped out the remaining non-avian dinosaurs.