Cenozoic Era summary

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Below is the article summary. For the full article, see Cenozoic Era.

Cenozoic Era, Third of the major eras of Earth history, and the interval of time during which the continents assumed their modern configurations and geographic positions. It was also the time when the Earth’s flora and fauna evolved toward those of the present. The Cenozoic, from the Greek for “recent life,” began c. 65.5 million years ago and is divided into three periods: the Paleogene (65.5–23 million years ago), Neogene (23–2.6 million years ago) and Quaternary (2.6 million years ago to the present).

Indricotherium, detail of a restoration painting by Charles R. Knight.

Oligocene Epoch Summary

Oligocene Epoch, third and last major worldwide division of the Paleogene Period (65.5 million to 23 million years ago), spanning the interval between 33.9 million to 23 million years ago. The Oligocene Epoch is subdivided into two ages and their corresponding rock stages: the Rupelian and the

Miocene Epoch Summary

Miocene Epoch, earliest major worldwide division of the Neogene Period (23 million years to 2.6 million years ago) that extended from 23 million to 5.3 million years ago. It is often divided into the Early Miocene Epoch (23 million to 16 million years ago), the Middle Miocene Epoch (16 million to

Holocene Epoch Summary

Holocene Epoch, younger of the two formally recognized epochs that constitute the Quaternary Period and the latest interval of geologic time, covering approximately the last 11,700 years of Earth’s history. The sediments of the Holocene, both continental and marine, cover the largest area of the

Pleistocene Epoch Summary

Pleistocene Epoch, earlier and major of the two epochs that constitute the Quaternary Period of Earth’s history, an epoch during which a succession of glacial and interglacial climatic cycles occurred. The base of the Gelasian Stage (2,588,000 to 1,800,000 years ago) marks the beginning of