The Miocene is a geological epoch that lasted from about 23 to 5.3 million years ago. The Miocene was the first epoch of the Neogene Period and followed the Oligocene Epoch. The Miocene is named after the Greek words μία (mia, meaning “one”) and καινός (kainos, meaning “new”), referring to the fact that it was the first period of the Cenozoic Era with a completely modern fauna.
The climate during the Miocene was warm and humid, with average global temperatures peaking around 15 °C (59 °F). This warm temperature regime is thought to have contributed to the rapid evolution of new lifeforms during this time. Mammals in particular experienced an evolutionary radiation, with new families and genera appearing throughout the epoch.
One of the most iconic animals of the Miocene is Andrewsarchus, a large carnivorous mammal that lived in what is now Mongolia. Andrewsarchus was one of the largest terrestrial predators ever known, measuring up to 6 m (20 ft) in length and weighing up to 1 tonne (2,200 lb). Another well-known animal from this time is Paraceratherium, an immense rhinoceros-like creature that roamed across Asia and North America. This beast could reach lengths of over 4 m (13 ft) and weigh up to 20 tonnes (44,000 lb)!
Other notable mammals from the Miocene include early apes such as Proconsul and Dryopithecus; early horses such as Equus; early elephants such as Elephas; early whales such as Basilosaurus; and early primates such as Notharctus. The world’s first penguins also appeared during this epoch. In short, nearly every modern group of mammals can trace its origins back to creatures that lived during this exciting time in Earth’s history!