The Early Miocene (also known as Lower Miocene) is a sub-epoch of the

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

Epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by ...

made up of two

stages Stage or stages may refer to: Acting * Stage (theatre), a space for the performance of theatrical productions * Theatre, a branch of the performing arts, often referred to as "the stage" * ''The Stage'', a weekly British theatre newspaper * S ...

: the Aquitanian and

Burdigalian The Burdigalian is, in the geologic timescale, an age (geology), age or stage (stratigraphy), stage in the early Miocene. It spans the time between 20.43 ± 0.05 annum, Ma and 15.97 ± 0.05 Ma (million years ago). Preceded by the Aquitanian (sta ...

stages. The sub-epoch lasted from 23.03 ± 0.05 Ma to 15.97 ± 0.05 Ma (million years ago). It was preceded by the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

epoch. As the climate started to get cooler, the landscape started to change. New mammals evolved to replace the extinct animals of the Oligocene epoch. The first members of the hyena and

weasel Weasels are mammals of the genus ''Mustela'' of the family Mustelidae. The genus ''Mustela'' includes the least weasels, polecats, stoats, ferrets and European mink. Members of this genus are small, active predators, with long and slender bo ...

family started to evolve to replace the extinct ''

Hyaenodon ''Hyaenodon'' ("hyena-tooth") is an extinct genus of carnivorous hyaenodont mammals from tribe Hyaenodontini, within subfamily Hyaenodontinae in family Hyaenodontidae,Malcolm C. McKenna, Susan K. Bell (1997."Classification of Mammals: Above the ...

'',

entelodont Entelodontidae, the entelodonts, are an extinct family of pig-like artiodactyls (even-toed ungulates) which inhabited the Northern Hemisphere (Asia, Europe, and North America) from the late Eocene to the Middle Miocene epochs, about 38-19 millio ...

s and bear-dogs. The chalicotheres survived the Oligocene epoch. A new genus of entelodont called ''

Daeodon ''Daeodon'' is an extinct genus of entelodont even-toed ungulates that inhabited North America about 23 to 20 million years ago during the latest Oligocene and earliest Miocene. The type species is ''Daeodon shoshonensis'', described by a ...

'' evolved in order to adapt to the new habitats and hunt the new prey animals of the Early Miocene epoch; it quickly became the top predator of

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

. But it became extinct due to

competition Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indivi ...

from '' Amphicyon'', a newcomer from

Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...

. ''Amphicyon'' bested ''Daeodon'' because the

bear-dog Amphicyonidae is an extinct family of terrestrial carnivorans belonging to the suborder Caniformia. They first appeared in North America in the middle Eocene (around 45 mya), spread to Europe by the late Eocene (35 mya), and appear in Asia, and ...

's larger brain, sharper teeth and longer legs built for longer chases helped it to overcome its prey.

External links

GeoWhen Database - Early Miocene
.01 Aquitanian (stage) Burdigalian 01 {{Geology-stub