Portal:Neogene

Topics Culture Geography Health History Mathematics Nature People Philosophy Religion Society Technology The Neogene Portal Template:/box-header The Neogene is a geologic period and system in the International Commission on Stratigraphy (ICS) Geologic Timescale starting 23.03 ± 0.05 million years ago and ending 2.588 million years ago. The second period in the Cenozoic Era, it follows the Paleogene Period and is succeeded by the Quaternary Period. The Neogene is subdivided into two epochs, the earlier Miocene and the later Pliocene. The Neogene covers about 20 million years. During this period, mammals and birds continued to evolve into roughly modern forms, while other groups of life remained relatively unchanged. Earlyhominids, the ancestors of humans, appeared in Africa. Some continental movement took place, the most significant event being the connection of North and South America at theIsthmus of Panama, late in the Pliocene. This cut off ocean currents between the Atlantic and Pacific oceans, causing climate changes and creating the Gulf Stream. The global climate cooled considerably over the course of the Neogene, culminating in a series of continental glaciations in the Quaternary Period that follows. (See more…) Template:/box-footer edit   Selected article on the Neogene world and its legacies Entoprocta is a phylum of mostly sessile marine animals, ranging from 0.1 to 7 millimetres (0.0039 to 0.2756 in) long. Mature individuals are goblet-shaped, on relatively long stalks. They have a "crown" of solid tentacles whose cilia generate water currents that draw food particles towards the mouth, and both the mouth and anus lie inside the "crown". Most families of entoprocts are colonial. Some species eject unfertilized ova into the water, while others keep their ova in brood chambers until they hatch, and some of these species use placenta-like organs to nourish the developing eggs. After hatching, the larvae swim for a short time and then settle on a surface. There they metamorphose, and the larval gut generally rotates by up to 180°, so that the mouth and anus face upwards. Both colonial and solitary species also reproduce by cloning – solitary species grow clones in the space between the tentacles and then release them when developed, while colonial ones produce new members from the stalks or from corridor-like stolons. Fossils of entoprocts are very rare, and the earliest specimens that have been identified with confidence date from the Late Jurassic. Most studies from 1996 onwards have regarded entoprocts as members of the Trochozoa, which also includes molluscs and annelids. However, a study in 2008 concluded that entoprocts are closely related to bryozoans. Recently, the Maotianshan Shales fossil,Cotyledion tylodes, has been reevaluated as being an ancient, sclerite-bearing entoproct. (see more...) edit   Selected article on the Neogene in human science, culture and economics On the Origin of Species, published in 1859, is a work of scientific literature by Charles Darwin which is considered to be the foundation of evolutionary biology. Darwin's book introduced the scientific theory that populations evolve over the course of generations through a process of natural selection. It presented a body of evidence that the diversity of life arose by common descent through a branching pattern of evolution. Darwin included evidence that he had gathered on the Beagle expedition in the 1830s and his subsequent research findings. Ideas about the transmutation of species were controversial as they conflicted with beliefs that species were unchanging parts of a designed hierarchy and that humans were unique and unlike animals. The book was written for non-specialist readers and attracted widespread interest upon its publication. As Darwin was an eminent scientist, his findings were taken seriously and the evidence he presented generated scientific, philosophical, and religious discussion. Within two decades there was widespread scientific agreement that evolution, with a branching pattern of common descent, had occurred, but scientists were slow to give natural selection the significance that Darwin thought appropriate. During the "eclipse of Darwinism" from the 1880s to the 1930s, various other mechanisms of evolution were given more credit. With the development of the modern evolutionary synthesis in the 1930s and 1940s, Darwin's concept of evolutionary adaptation through natural selection became central to modern evolutionary theory, and it has now become the unifying concept of the life sciences. (see more...) edit   Selected picture Laelaps by Charles R. Knight. The painting Laelaps by Charles R. Knight depicts two Dryptosaurus fighting. Photo credit: User:Sergiodlarosa edit   Did you know? Holotype specimen of Oligochlora semirugosa preserved in amber. ... that the extinct sweat bee genus Oligochlora contains six species all known from the Dominican amber deposits on Hispaniola? ... that the fossil horse Scaphohippus became extinct when tectonic barriers between the Great Plains and Great Basin of North America disappeared about 13 million years ago? ... that the only male "sweat bee" to have been documented from Dominican amber is the type specimen for the extinct Eickwortapis? ... that unlike living rorqual whales, the late Miocene genus Plesiobalaenoptera was probably not capable of ram feeding? ... that a fossil flower of the extinct palm Roystonea palaea shows damage possibly made by a bat or bird? Template:/box-header Geochronology - Cambrian (Early - Middle - Late) - Ordovician (Early - Middle - Late) - Silurian (Early - Wenlock - Ludlow - Late) - Devonian (Early - Middle - Late) - Carboniferous (Mississippian - Pennsylvanian)- Permian (Early - Middle - Late) Paleozoic landmasses - Pannotia - Baltica - Laurentia - Siberia - Avalonia -Gondwanaland - Laurentia - Euramerica - Gondwana - South China- Pangaea Major Paleozoic events - Cambrian Explosion - Cambrian substrate revolution - End-Botomian mass extinction - Cambrian–Ordovician extinction event Cambrian appearances - Brachiopods - Burgess shale fauna - Cephalopods - Chitons - Crustaceans - Echinoderms - Foraminiferans - Graptolites - Radiolarians -Trilobites - Vertebrates Ordovician appearances - Conodonts - Echinoids Silurian appearances - Fungi - Galeaspids - Heterostracans - Land plants - Pituriaspids -Ray-finned fishes - Scorpions - Trigonotarbids Devonian appearances - Crabs - Ferns - Harvestmen - Lichens - Lycophytes - Mites -Springtails - Stoneworts - Trimerophytes Carboniferous appearances - Amphibians - Hagfishes - Insects - Ratfishes - Reptiles -Synapsids Permian appearances - Beetles - Pelycosaurs - Temnospondyls - Therapsids Fossil sites - Bear Gulch Limestone - Beecher's Trilobite Bed - Gilboa Forest - Grenfell fossil site - Hamilton Quarry - Mazon Creek fossil beds - Mississippi Petrified Forest - Paleorrota - Walcott Quarry - Walcott–Rust quarry - Yea Flora Fossil Site Stratigraphic units - Burgess Shale - Chazy Formation - Columbus Limestone - Fezouata formation - Francis Creek Shale - Gogo Formation - Holston Formation - Hunsrück Slate - Jeffersonville Limestone - Karoo Supergroup - Keyser Formation - Kope Formation - Llewellyn Formation - Mahantango Formation - Maotianshan Shales - Marcellus Formation - Millstone Grit - New Albany Shale - Old Port Formation - Old Red Sandstone - Potsdam Sandstone - Red Beds of Texas and Oklahoma - Rhynie chert - Shawangunk Formation - St. Peter Sandstone - Tuscarora Formation History - History of paleontology - Timeline of paleontology - The Great Devonian Controversy Researchers - Charles Emerson Beecher - Ermine Cowles Case - Edward Drinker Cope - Henry De la Beche - Stephen Jay Gould - Increase A. Lapham - Charles Lapworth - Simon Conway Morris - Roderick Murchison - Alfred Sherwood Romer - Neil Shubin - Charles Doolittle Walcott Culture - Animal Armageddon - The Day The Earth Nearly Died - List of creatures in the Walking with... series - Lost Worlds, Vanished Lives - Miracle Planet - Prehistoric Park - Sea Monsters - Treatise on Invertebrate Paleontology - Vertebrate Paleontology - Walking with Monsters - Wonderful Life Template:/box-footer Template:/box-header Featured Neogene articles - Good Neogene articles - Template:/box-footer ► Neogene no subcategories Here are some tasks awaiting attention: Stubs : Neogene stubs, Current Neogene FACs - none currently Template:/box-footer Time Earth sciences Paleontology Extinct and Endangered Species Paleozoic Mesozoic Cenozoic Paleogene Quaternary What are portals? List of portals Featured portals