-Plants began spreading beyond the wetlands, stemmed plants evolved strong
-Otherwise known as the Age of Fishes, shark ancestors, the first amphibians breathed through simple lungs and their skin.
- The great supercontinent of Gondwana was headed steadily northward, away from the South Pole, and a second supercontinent began to form that straddled the equator.
-Mean atmospheric O
2 content over period duration ca. 15 Vol %[1]
(75 % of modern level)
