Pliocene

American  

[plahy-uh-seen] / ˈplaɪ əˌsin /

adjective

1. noting or pertaining to an epoch of the Tertiary Period, occurring from 10 to 2 million years ago, and characterized by increased size and numbers of mammals, by the growth of mountains, and by global climatic cooling.

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noun

1. the Pliocene Epoch or Series.

Pliocene British  

/ ˈplaɪəʊˌsiːn /

adjective

1. of, denoting, or formed in the last epoch of the Tertiary period, which lasted for three million years, during which many modern mammals appeared

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noun

1. the Pliocene epoch or rock series

Pliocene Scientific  

/ plī′ə-sēn′ /

1. The fifth and last epoch of the Tertiary Period, from about 5 to 2 million years ago. During this time the global climate became cooler and the number and expanse of grasslands and savannas increased greatly. This change in vegetation was accompanied by an increase in long-legged grazers. The land bridge between North America and South America also formed at this time, and massive ice sheets accumulated at the poles. In the later part of the epoch many of the species living in polar regions became extinct.

2. See Chart at geologic time

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Other Word Forms

• post-Pliocene
  adjective

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Etymology

Origin of Pliocene

First recorded in 1825–35; plio- + -cene

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Example Sentences

See Examples For:

Pliocene

The bones were preserved in the Tsubusugawa Formation, a layer of ancient lake sediments from the Pliocene dating to about 3.5 million years ago.

From Science Daily ● Jul. 24, 2026

These cores, as wide as a dinner plate, yielded hundreds of samples of ancient air—including the first ever from the Pliocene, which ended about 2.6 million years ago with the start of the ice ages.

From Science Magazine ● Apr. 21, 2024

Bones and teeth of a considerably older sloth, Megalonyx leptostomus, also have been found in Pliocene sediments in Eastern Washington, dated around 4.9 million years old.

From Seattle Times ● Sep. 15, 2023

The diversity of foot forms found in Pliocene fossil sites across the continent supports such a scenario.

From Scientific American ● Nov. 5, 2022

The subgenera Otisorex and Sorex probably separated in early Pleistocene or late Pliocene.

From Speciation of the Wandering Shrew by James S. Findley

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