Oligocene

American  

[ol-i-goh-seen] / ˈɒl ɪ goʊˌsin /

adjective

1. noting or pertaining to an epoch of the Tertiary Period, occurring from 40 to 25 million years ago.

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noun

1. the Oligocene Epoch or Series.

Oligocene British  

/ ɒˈlɪɡ-, ˈɒlɪɡəʊˌsiːn /

adjective

1. of, denoting, or formed in the third epoch of the Tertiary period, which lasted for 10 000 000 years

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noun

1. the Oligocene epoch or rock series

Oligocene Scientific  

/ ŏl′ĭ-gō-sēn′ /

1. The third epoch of the Tertiary Period, from about 37 to 24 million years ago. During this time there was an increase in volcanic activity, and Australia and South America separated from Antarctica. The climate started to cool and a glacier started to form in Antarctica. Modern mammalian groups continued to develop, and the first cats, dogs, horses, and related mammals appeared. Artiodactyls (even-toed ungulates) took over from the perissodactyls (uneven-toed ungulates) as the dominant medium-sized herbivores. Many types of grass also first appeared at this time.

2. See Chart at geologic time

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Other Word Forms

• post-Oligocene adjective

Etymology

Origin of Oligocene

First recorded in 1855–60; oligo- + -cene

Example Sentences

It started with a period of glaciation that must have been a chilly change from the greenhouse-like Oligocene, and ended with a prolonged period of glaciation, too.

From Salon

The Gibraltar arc formed in the Oligocene as a part of the Western Mediterranean subduction zones.

From Science Daily

It represents a segment of a population tracing its ancestry back to the widespread Oligocene ancestor, approximately 28 million years ago, in the Philippines.

From Science Daily

The report includes an understated, but nonetheless pointed, criticism of the paltriness of scientific literature about North Pacific odontocetes species from the Oligocene epoch, which lasted roughly from 33.7 to 23.8 million years ago.

From Salon

As the Eocene gave way to the Oligocene, tectonic forces dealt a final blow to Gondwana, cleaving apart Australia, South America and Antarctica.

From Scientific American