4. Why are the time periods of the Paleozoic and Mesozoic subdivided into early, middle, and late instead of named epochs, as they are in the Cenozoic? O The rocks of these time periods are too young to provide sufficient data to subdivide the periods based on the ages of rocks.
O The fossil record for the Paleozoic and Mesozoic eras is not sufficient to subdivide the periods based on the presence of organisms.
O The number of fossils discovered outnumbers the quantity needed to subdivide the periods based on the presence of organisms.
O The terms early, middle, and late are easier to remember, which removes some confusion for those studying the geologic time scale. We