The Carboniferous began 358 million years ago, and it ended 298 million years ago. It was the period when large forests grew, and they caused the large coal deposits and a high oxygen level. A huge diversity of corals, echinoderms and brachiopods existed. Large single-celled forams lived on the seafloor. Sharks and bony fishes swam around in the water. On land, large forests with clubmosses, horsetails, ferns and early seed plants grew up and they were lifeplaces of huge insects and large amphibians. The first reptiles emerged. The climate was very similar like today and there was an ice age again.
On the picture, you can see corals, brachiopods, trilobites and other sea life on the seafloor. There are also crinoids and blastoids. Above them, ammonites, different fishes and the Tully monster are swimming. In the background, there is a forest with spore plants like Lepidodendron, Sigillaria, Calamites and Psaronius. There are also seed plants like Medullosa. In this forest, you can see the dragonfly Meganeura, the millipede Arthropleura, some amphibians and the early reptile Hylonomus.