Earth is currently in the Holocene Epoch. In geologic time , the Holocene Epoch represents the second epoch in the current Quaternary Period (also termed the Anthropogene Period) of the current Cenozoic Era of the ongoing Phanerozoic Eon . The Holocene Epoch ranges from approximately 10,000 years ago until present day.
Also termed the Recent Epoch, the Holocene Epoch is thus far notable for the retreat of glaciers—a major force in producing the landscape topographical features evident today—and the geological time during which humans (Homo sapiens ) became the dominant life form on Earth, increased their societal relationships, and produced major civilizations. The retreat of glaciers and the gradual climactic warming in the Northern Hemisphere encouraged migration and biological radiation of species.
Although Homo sapiens appeared during the preceding Pleistocene Epoch , and were fully differentiated as a species by the beginning of the Holocene Epoch, human societal evolution has taken place during the Holocene Epoch. As expected, the most recent and superficial of sedimentary remains were laid down during the Holocene Epoch. The fossil record is also dotted with an archaeological record of human activity and civilization.
Human societal and intellectual development during the Holocene Epoch produced the first species capable of significantly and consciously altering geophysical processes. In addition to deliberate reworking of topographical features and use of natural resources, byproducts of human civilization and industrialization have affected groundwater reservoirs, the type of abundance of weathering agents, the geochemistry of atmospheric processes on a local scale (e.g., acid rain ); and possible atmospheric and/or marine processes on a global scale (e.g., possible global warming ).
The general retreat of glaciation was punctuated by smaller-scale "ice ages"—including the "Little Ice Age" that occurred between approximately 1150 and 1700. One of the reasons that it is difficult for modern scientists to quantify the possible extent in global warming is that accurate climatic data extends back, at best, only about a hundred years. Accordingly, it is difficult to determine whether any data indicating global warming is simply a normal variation in a general downtrend, or a normal variation in generalized warming pattern.
See also Archean; Cambrian Period; Cretaceous Period; Dating methods; Devonian Period; Eocene Epoch; Evolution, evidence of; Fossil record; Fossils and fossilization; Geologic time; Historical geology; Holocene Epoch; Jurassic Period; Mesozoic Era; Miocene Epoch; Mississippian Period; Oligocene Epoch; Ordovician Period; Paleocene Epoch; Paleozoic Era; Pennsylvanian Period; Pliocene Epoch; Precambrian; Proterozoic Era; Silurian Period; Supercontinents; Tertiary Period; Triassic Period
Holocene epoch (hŏl´əsēn) 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 accepted by geologists. There is 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.AD 900 or with the Industrial Revolution.
See Geologic Timescale (table).