User:Abyssal/Portal:Ediacaran

The Ediacaran Portal Introduction Selected article on the Ediacaran world and its legacies Artist's reconstruction of Waptia fieldensis. The evolutionary history of life on Earth traces the processes by which living and fossil organisms have evolved since life on the planet first originated until the present day. Earth formed about 4.5 Ga (billion years ago) and life appeared on its surface within one billion years. Microbial mats of coexisting bacteria and archaea were the dominant form of life in the early Archean. The evolution of oxygenic photosynthesis, around 3.5 Ga, eventually led to the oxygenation of the atmosphere, beginning around 2.4 Ga. The earliest evidence of eukaryotes (complex cells with organelles), dates from 1.85 Ga, and while they may have been present earlier, their diversification accelerated when they started using oxygen in their metabolism. Later, around 1.7 Ga, multicellular organisms began to appear, with differentiated cells performing specialised functions. The earliest land plants date back to around 450 Ma (million years ago), although evidence suggests that algal scum formed on the land as early as 1.2 Ga. Land plants were so successful that they are thought to have contributed to the late Devonian extinction event. Invertebrate animals appear during the Vendian period, while vertebrates originated about525 Ma during the Cambrian explosion. During the Permian period, synapsids, including the ancestors of mammals, dominated the land, but the Permian–Triassic extinction event251 Ma came close to wiping out all complex life. (see more...) Selected article on the Ediacaran in human science, culture and economics A Marella fossil. Paleontology or palaeontology (/ˌpeɪliɒnˈtɒlədʒi, ˌpæli-, -ən-/) is the scientific study of prehistoric life. It includes the study of fossils to determine organisms' evolution and interactions with each other and their environments (their paleoecology). As a "historical science" it attempts to explain causes rather than conduct experiments to observe effects. Paleontological observations have been documented as far back as the 5th century BC. The science became established in the 18th century as a result of Georges Cuvier's work on comparative anatomy, and developed rapidly in the 19th century. The term itself originates from Greek: παλαιός (palaios) meaning "old, ancient," ὄν, ὀντ- (on, ont-), meaning "being, creature" and λόγος (logos), meaning "speech, thought, study". Paleontology lies on the border between biology and geology. It now uses techniques drawn from a wide range of sciences, including biochemistry, mathematics and engineering. Use of all these techniques has enabled paleontologists to discover much of the evolutionary history of life, almost all the way back to when Earth became capable of supporting life, about 3,800 million years ago. As knowledge has increased, paleontology has developed specialized sub-divisions, some of which focus on different types of fossil organisms while others study ecology and environmental history, such as ancient climates. Body fossils and trace fossils are the principal types of evidence about ancient life, and geochemical evidence has helped to decipher the evolution of life before there were organisms large enough to leave fossils. (see more...) Selected image Agnostus pisiformis (Linnaeus, 1757) as depicted in the 47th plate of Ernst Haeckel's Kunstformen der Natur.. Photo credit: User:Micha L. Rieser Did you know? Spriggina flounensi ...that the enigmatic Ediacaran biota (fossil pictured) have been classified into every major group of lifeforms, including their own kingdom? ... that fossils of Yelovichnus were initially believed to be the feeding trails of other organisms? ... that the last common ancestor of bilaterian animals has been reconstructed as a tiny worm with a combined mouth and anus? ... that Andiva (fossil pictured), an enigmatic animal that lived 555 millions of years ago, perhaps had a convex carapace? Geochronology Series - Terreneuvian - Cambrian Series 2 - Cambrian Series 3 - Furongian Epochs - Early Cambrian - Middle Cambrian - Late Cambrian Stages - Fortunian - Cambrian Stage 2 - Cambrian Stage 3 - Cambrian Stage 4 - Cambrian Stage 5 - Drumian - Guzhangian -Paibian - Jiangshanian - Cambrian Stage 10 Events - Cambrian Explosion - Cambrian substrate revolution - End-Botomian mass extinction - Cambrian–Ordovician extinction event Geography - Pannotia - Baltica - Gondwanaland - Laurentia - Siberia Animals - Archaeocyathans - Trilobites Trace fossils - Climactichnites - Protichnites Plants - Dalyia - Margaretia Fossil sites - Walcott Quarry Stratigraphic units - Burgess Shale - Maotianshan Shales Researchers - Stephen Jay Gould - Simon Conway Morris - Charles Doolittle Walcott Culture - Wonderful Life (book) Quality Content Featured Cambrian articles - None Good Cambrian articles - Fossils of the Burgess Shale - Opabinia - Small shelly fauna - Stephen Jay Gould - Waptia Subcategories Ediacaran Ediacaran Africa Ediacaran Asia Ediacaran Europe Ediacaran North America Ediacaran South America Ediacaran events Ediacaran geology Ediacaran life Ediacaran paleogeography Placozoa Vendobionta Things you can do Here are some tasks awaiting attention: Stubs : Cambrian stubs Current Cambrian FACs - none currently Related content Time Earth sciences Paleontology Extinct and Endangered Species Paleozoic Cambrian Ordovician Silurian Devonian Carboniferous Permian Associated Wikimedia The following Wikimedia Foundation sister projects provide more on this subject: Commons Free media repository Wikibooks Free textbooks and manuals Wikidata Free knowledge base Wikinews Free-content news Wikiquote Collection of quotations Wikisource Free-content library Wikiversity Free learning tools Wiktionary Dictionary and thesaurus ¤ 01 Category:Geologic time portals