miocene

And they are known from the late Miocene, about eight million years ago.

Stupendemys lived about 7-13 million years ago during the Miocene Epoch near modern South America.

Discokeryx lived in open grasslands with small groups of trees during a time known as the Miocene period.

Paleoanthropologists found the newly identified diurnal owl lived around 6 million years ago in the late Miocene period.

This major climatic shift likely caused the extinction of many Miocene ape lineages.

Many other lineages of apes thrived during the Miocene.

So what caused this really bad day in the Miocene?

Now, being so big probably helped them deal with large Miocene predators, like saber-toothed barbourofelids.

The largest are the thunderbirds called Dromornis stirtoni. And they are known from the late Miocene, about eight million years ago.

So, as they became increasingly adapted to their grassy new environment, equines thrived throughout the Miocene.