-
570 BCE
Cambrian
-
488 BCE
Ordovician
a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.2 million years from the end of the Cambrian Period 485.4 (mya) -
443 BCE
Silurian
-
419 BCE
Devonian
The first significant adaptive radiation of life on dry land occurred during the Devonian -
359 BCE
Carboniferous
-
299 BCE
Permian