Ferns, seed ferns and giant lycopods.
Image: Walter Myers
340 million years ago
Image: Ron Blakey. Altered by Cally Bennet and Fons VandenBerg
Source: Colorado Plateau Geosystems
Land plants were developing strong root systems that allowed them to grow larger and occupy drier land. Trees were growing taller, and beneath their canopy new environments began to evolve. The copious plant life was literally changing the atmosphere, as the abundant trees pumped more oxygen into the air. These swampy forests were preserved as major coal beds in Europe and North America, giving the Carboniferous Period its name. While giant millipedes lived on the forest floor and giant insects took to the air, amphibious tetrapods became diverse – some became more adapted to spending more time on land, while others returned to the water. From the tetrapods evolved another group of land vertebrates – the early reptiles.
Australia, as part of Gondwana, drifted on its tectonic plate from near the equator to near the south pole, gradually becoming colder. Unlike the forests forming coal in other parts of the world, the vegetation was more slow-growing and adapted to a cool climate. The fossils show a transition from giant club-mosses to seed ferns. There are few fossils from Victoria at this time to give clues to the life on land.