
During the Ordovician period, life expanded in diversity tremendously. After a mass extinction event, the Devonian period began and fish flourished.
The Devonian period between 419 and 358 million years ago, which has been dubbed the Age of Fishes, saw aquatic life reach diversity and plants beginning to spread across dry land.
There was no plant nor animal life on land, but invertebrates and arthropods dominated the oceans during the Ordovician period of 485.4 to 443.8 million years ago.