Age of FishFish had obtained scales and jaws, like the ones today. They took their place in reefs containing nautiloids, corals, graptolites, blastods, echnioderms, trilobites, sponges, brachiopods, and conodonts.
Plants finally started to develop, like ferns, moss, and seeded plants. Trees at the beginning of the devonian were small and primitive, but by the end they were large, tall rooted structures covered in leaves.Insects also developed, and amphibians tried to make their way onto land. The Late Devonian extinctionThe late Devonian extinction was one of the 5 major mass extinctions, 50% of all genera went extinct when carbon dioxide plunged the world into a ice age very similar to the Pleistocene ice age.
GeologyDuring the Devonian, there were two supercontinents, Gondwana and Euramerica, located relatively close to each other in the Southern Hemisphere.
A vast ocean covered the rest of the globe. The closure of the oceans between Gondwana and Euramerica led to creation of Pangaea, which continued into the Mezozoic. ClimateThe land was comparatively arid. Global climate was relatively warm and dry, and there was less of an equator-to-pole temperature gradient than today.
There were no glaciers until the Late Devonian, when ice began to cover parts of the South Polar region. |
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