Oligocene Epoch
34-23 million years ago
The Oligocene was a time of global cooling as Antarctica began to glaciate. Forests shrank, grasslands expanded, and mammals adapted to cooler, more open environments. Many of the recognizable ancestors of today's animals, from rhinos to early cats, lived during this epoch.
Fun Facts
- âAntarctica began developing a permanent ice sheet during the Oligocene.
- âParaceratherium, the largest land mammal ever, lived during the Oligocene and was related to modern rhinos.
- âEarly cats and dogs both appeared during the Oligocene.
- âThe global cooling of the Oligocene drove many tropical species extinct and favored cold-tolerant animals.