What are the five eras in Earth's history?
Feb 5, 2018
Paleozoic, Mesozoic, and Cenozoic
Paleozoic Era - "ancient life" (such as trilobites).
Mesozoic Era - "middle life" (such as dinosaurs).
Cenozoic Era - "recent life" (such as mammals and flowering plants).
There are only 3 commonly accepted eras.