Portal:Devonian
The Devonian Portal The Devonian period experienced the first significant adaptive radiation of terrestrial life. Since large vertebrateterrestrial herbivores had not yet appeared, free-sporingvascular plants began to spread acrossdry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the firstseed-bearing plants appeared. Various terrestrial arthropods also became well-established. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the "Age of Fish". The first ray-finned and lobe-finned bony fish appeared, while the placoderms began dominating almost every known aquatic environment. The ancestors of all tetrapods began adapting to walking on land, their strong pectoral and pelvic fins gradually evolved into legs. In the oceans, primitive sharks became more numerous than in the Silurian and the late Ordovician. The firstammonite mollusks appeared.Trilobites, the mollusk-like brachiopods and the great coral reefs, were still common. The Late Devonian extinction severely affected marine life, killing off all placoderms, and all trilobites, save for a few species of the order Proetida. The paleogeography was dominated by the supercontinent of Gondwana to the south, the continent of Siberia to the north, and the early formation of the small continent of Euramerica in between. Lua error in package.lua at line 80: module 'Module:Box-header/colours' not found.  Lua error in package.lua at line 80: module 'Module:Box-header/colours' not found. The history of paleontology traces the history of the effort to study the fossil record left behind by ancient life forms. Although fossils had been studied by scholars since ancient times, the nature of fossils and their relationship to life in the past became better understood during the 17th and 18th centuries. At the end of the 18th century the work of Georges Cuvier ended a long running debate about the reality of extinction and led to the emergence of paleontology as a scientific discipline.The first half of the 19th century saw paleontological activity become increasingly well organized. This contributed to a rapid increase in knowledge about the history of life on Earth, and progress towards definition of the geologic time scale. As knowledge of life's history continued to improve, it became increasingly obvious that there had been some kind of successive order to the development of life. After Charles Darwin published Origin of Species in 1859, much of the focus of paleontology shifted to understanding evolutionary paths. The last half of the 19th century saw a tremendous expansion in paleontological activity, especially in North America. The trend continued in the 20th century with additional regions of the Earth being opened to systematic fossil collection, as demonstrated by a series of important discoveries in China near the end of the 20th century. There was also a renewed interest in the Cambrian explosion that saw the development of the body plans of most animal phyla. (see more...) Lua error in package.lua at line 80: module 'Module:Box-header/colours' not found.
Photo credit: Mark A. Wilson Lua error in package.lua at line 80: module 'Module:Box-header/colours' not found. 
Template:/box-header Epochs - Early Devonian - Middle Devonian - Late Devonian Landmasses - Baltica - Laurentia - Euramerica - Gondwana Fossil sites - Grenfell fossil site History - The Great Devonian Controversy Template:/box-header Featured Devonian articles - None
Current Devonian FACs - none currently
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