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| This epoch is part of the Tertiary period and the Neogene subperiod. |
| Pliocene |
| Miocene |
| Oligocene |
| Eocene |
| Paleocene |
The Pliocene epoch is the period in the geologic timescale that extends from about 5 million to 1.8-1.6 million years before present.
The Pliocene follows the Miocene epoch and is followed by the Pleistocene epoch. The Pliocene is the fifth and last epoch of the Tertiary Era.
As with other older geologic periods, the rock beds that define the start and end are well identified, but the exact dates of the start and end of the epoch are slightly uncertain. The Pliocene was named by Sir Charles Lyell. The name means roughly "continuation of recent", and refers to the essentially modern mammalian faunas.
The Pliocene boundaries are not set at an easily identified worldwide event but rather at regional boundaries between the warmer Miocene and the relatively cooler Pliocene. The upper boundary was intended to be set at the start of the Pleistocene glaciations but is now considered to be set too late.
The Pliocene faunal stages from youngest to oldest are:
Climates became cooler and drier, and seasonal, simmilar to modern climates. Antarctica became ice-bound near or before the start of the Pliocene. Mid-latitude glaciations were probably underway before the end of the epoch; the ArcticThe Arctic is the area around the Earth's North Pole. The Arctic includes parts of Russia, Alaska, Canada, Greenland, Lapland, and Norway (including Svalbard), as well as the Arctic Ocean. The 10°C (50°F) July isotherm is commonly used to define the borde ice cap formed, and Antarctica was covered entriely with year-round glaciation by the end of the period.
Continents continued to drift20th century. Plate tectonics (from the Greek word for "one who constructs", τεκτων tekton ) is a theory of geology developed to explain the phenomenon of continental drift. In the theory of plate tectonics the outermost par toward their present positions, moving from positions possibly as far as 250km from their present locations to positions only 70 km from their current locations. South America became linked to North America through the Isthmus of Panama during the Pliocene, bringing a nearly complete end to South America's distinctive marsupial faunas. The formation of teh Isthmus would have major consequences on global temperatures, as warm equatorial ocean currents were cut off and an Atlantic cooling cycle began, with cold Arctic and Antarctic waters dropping temperatures in the now-isolated Atlantic ocean.
Africa's collision with Europe formed the Mediterranian sea, cutting off the Tethys Ocean.
Sea level changes exposed the land-bridge between Alaska and Asia.
Pliocene marine rocks are well exposed in the Mediterranean, India, and China. Elsewhere, they are exposed largely near shores.
The change to a cooler, dry, seasonal climate had considerable impacts on pliocene vegetation, reducing tropical species world-wide. DeciduousDeciduous means "temporary" or "tending to fall off". Deciduous plants are those that lose their foliage for part of the year. In most cases, the foliage loss coincides with the incidence of winter in temperate or polar climates, but some plants lose thei forests proliferated, coniferous forests and tundraIn physical geography, tundra is an area where tree growth is hindered by low temperatures and short growing seasons. The term tundra comes from the Finnish word tunturia which means treeless plain. There are three types of tundra: arctic tundra antarctic covered much of the north, and grasslands opeded up all continents (except Antarctica). Tropical forests were limited to a tight band around the equator, and in addition to dry savannahs, deserts appeared in Asia and Africa.
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