System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
Quaternary Pleistocene Gelasian younger
Neogene Pliocene Piacenzian 2.58 3.600
Zanclean 3.600 5.333
Miocene Messinian 5.333 7.246
Tortonian 7.246 11.63
Serravallian 11.63 13.82
Langhian 13.82 15.97
Burdigalian 15.97 20.44
Aquitanian 20.44 23.03
Paleogene Oligocene Chattian older
Subdivision of the Neogene Period
according to the ICS, as of 2017.[1]

The Miocene ( /ˈm.əˌsn, ˈm.-/ MY-ə-seen, MY-oh-[2][3]) is the first geological epoch of the Neogene Period and extends from about 23.03 to 5.333 million years ago (Ma). The Miocene was named by Charles Lyell; its name comes from the Greek words μείων (meiōn, "less") and καινός (kainos, "new")[4][5] and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene.[6] The Miocene is preceded by the Oligocene and is followed by the Pliocene.

As the earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch.

The apes first evolved, arose, and diversified during the early Miocene (Aquitanian and Burdigalian stages), becoming widespread in the Old World. By the end of this epoch and the start of the following one, the ancestors of humans had split away from the ancestors of the chimpanzees to follow their own evolutionary path during the final Messinian stage (7.5–5.3 Ma) of the Miocene. As in the Oligocene before it, grasslands continued to expand and forests to dwindle in extent. In the seas of the Miocene, kelp forests made their first appearance and soon became one of Earth's most productive ecosystems.[7]

The plants and animals of the Miocene were recognizably modern. Mammals and birds were well-established. Whales, pinnipeds, and kelp spread.

The Miocene is of particular interest to geologists and palaeoclimatologists as major phases of the geology of the Himalaya occurred during the Miocene, affecting monsoonal patterns in Asia, which were interlinked with glacial periods in the northern hemisphere.[8]

Subdivisions

Subdivisions of the Miocene

The Miocene faunal stages from youngest to oldest are typically named according to the International Commission on Stratigraphy:[9]

Sub-epoch Faunal stage Time range
Late Miocene Messinian 7.246–5.333 Ma
Tortonian 11.608–7.246 Ma
Middle Miocene Serravallian 13.65–11.608 Ma
Langhian 15.97–13.65 Ma
Early Miocene Burdigalian 20.43–15.97 Ma
Aquitanian 23.03–20.43 Ma

Regionally, other systems are used, based on characteristic land mammals; some of them overlap with the preceding Oligocene and following Pliocene epochs:

European Land Mammal Ages

North American Land Mammal Ages

South American Land Mammal Ages