Holocene epoch

Holocene epoch hŏlˈəsēn [key] or Recent epoch, most recent of all subdivisions of geologic time, ranging from the present back to the time (c.11,000 years ago) of almost complete withdrawal of the glaciers of the preceding Pleistocene epoch. During the Holocene epoch, the sculpturing of the earth's surface to its present form was completed. Withdrawal of the glacial ice resulted in the development of the present-day drainage basins of the Missouri and Ohio rivers, the development of the Great Lakes, and a global rise in sea level of up to 100 ft (30 m) as the glacial meltwater was returned to the seas. Warming climates resulted in the poleward migration of plants and animals.

The most significant development during the Holocene was the rise of modern humans, who are thought to have first appeared in the late Pleistocene. All of the races of modern humans were fully developed, with eventual worldwide distribution. Human culture developed during this epoch from a primitive one to the complex industrial society of today, in which humans themselves have become a significant factor in altering the earth's surface environment. As a result of extensive human influence on the environment, some have argued that “Anthropocene epoch” should be used instead of Holocene epoch for recent time, but the term has not been formally accepted by geologists. There has been disagreement even among advocates of the use of the term concerning when the Anthropocene should be considered to have begun, with some suggesting that the entire Holocene Epoch be renamed, and others suggesting that the Anthropocene began c.a.d. 900 or with the Industrial Revolution. In 2019 a working group recommended that the International Geological Congress declare the Anthropocene Epoch, with a beginning date of c.1950; a final decision will be made after the working group determines the geological markers for the epoch.

See Geologic Timescale (table)geologic timescale (table).

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