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Aspidella
:Aspidella'' is also a homonym for the mushroom genus '' Saproamanita. ''Aspidella'' is an Ediacaran disk-shaped fossil of uncertain affinity. It is known from the single species ''A. terranovica''. Morphology ''Aspidella'' consists of disk-shaped fossils, with concentric rings and/or centripetal rays. The diameter of circular ''Aspidella'' varies from 1 to 180 mm.Peterson. P. 131 Most individuals are between 4 and 10 mm, but smaller individuals would presumably have decayed before they could fossilize. Other ''Aspidella'' take the form of ellipses, 3–8 cm long and 1–4 cm wide. Most have a central pimple. The rim of all specimens is made up by ridge-edged rays and/or concentric rings. Ecology The rarity of large individuals probably indicates that ''Aspidella'' were r-strategists, producing numerous offspring of which most died young. It is most common in deep-water sediments, but is a constituent of most Ediacaran fossil assemblages, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspidella Specimens
:Aspidella'' is also a homonym for the mushroom genus ''Saproamanita. ''Aspidella'' is an Ediacaran disk-shaped fossil of uncertain affinity. It is known from the single species ''A. terranovica''. Morphology ''Aspidella'' consists of disk-shaped fossils, with concentric rings and/or centripetal rays. The diameter of circular ''Aspidella'' varies from 1 to 180 mm.Peterson. P. 131 Most individuals are between 4 and 10 mm, but smaller individuals would presumably have decayed before they could fossilize. Other ''Aspidella'' take the form of ellipses, 3–8 cm long and 1–4 cm wide. Most have a central pimple. The rim of all specimens is made up by ridge-edged rays and/or concentric rings. Ecology The rarity of large individuals probably indicates that ''Aspidella'' were r-strategists, producing numerous offspring of which most died young. It is most common in deep-water sediments, but is a constituent of most Ediacaran fossil assemblages, including thos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saproamanita
The genus ''Saproamanita'' contains about 24 species of agarics and is one of six genera in the family Amanitaceae. The others are ''Amanita'' (which now includes the synonym ''Torrendia'', a generic name previously applied to sequestrate species), ''Catatrama'', ''Limacellopsis'', ''Zhuliangomyces'' and ''Limacella''. ''Saproamanita'' are the saprophytic species in the Tribe Amaniteae, separately classified from the ectomycorrhizal species in the genus ''Amanita''. ''Saproamanita'' resemble ''Amanita'' and have a pileus, free lamellae, a central stipe, and an annulus with scales and rings below the annulus that are the remnants of the universal veil composed largely of cylindrical to slender clavate inflated hyphal cells mostly scattered in the central stipe region rather than the base. The spores are white and amyloid. DNA molecular evidence for the separation of the saprotrophic genus from the sister genus of symbiotic genus ''Amanita'' was first detected in a study of mushro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaria
''Ediacaria'' is a fossil genus dating to the Ediacaran Period of the Neoproterozoic Era. Unlike most Ediacaran biota, which disappeared almost entirely from the fossil record at the end of the Period, ''Ediacaria'' fossils have been found dating from the Baikalian age (850–650 Ma) of the Upper Riphean to 501 million years ago, well into the Cambrian Period. ''Ediacaria'' consists of concentric rough circles, radial lines between the circles and a central dome, with a diameter from 1 to 70 cm. Systematics and taxonomy ''Ediacaria'' was named by Reg Sprigg in 1947, after the Ediacara Hills in South Australia. Two species are recognised: ''E. flindersi'', described by Sprigg from the Pound Quartzite in the Ediacara Hills, and ''E. booleyi'', described in 1995 from a Late Cambrian deposit at Booley Bay (County Wexford), Ireland. The species were named after the Flinders Ranges and Booley Bay, respectively. ''Ediacaria'' is possibly a synonym for ''Aspidella ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fermeuse Formation
The Fermeuse Formation is a fossil-bearing Ediacaran geologic formation in Newfoundland. Palaeobiological community On Avalon Peninsula there is low diversity, and includes rare trace fossils, ''Palaeopascichnus'', and ''Aspidella'' discs, sometimes in great concentrations. On Bonavista Peninsula there is higher diversity, including more fronds (rangeomorphs) and better preserved than on Avalon Peninsula. Depositional environment On Bonavista Peninsula the depositional environment was a slope and outer shelf–below photic zone Turbidites probably were the dominant sediment transporters. It is predominantly silts and sands, in contrast to underlying Trepassey Formation, which is mostly dark grey shales. There is a coarsening up sequence throughout the two formations, such that the top of the Fermeuse is predominantly sandstones. On Avalon Peninsula there were much shallower waters, particularly than in underlying Mistaken Point Formation and Trepassey Formation. It is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran Biota
The Ediacaran (; formerly Vendian) biota is a taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (). These were composed of enigmatic tubular and frond-shaped, mostly sessile, organisms. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms. The Ediacaran biota may have undergone evolutionary radiation in a proposed event called the Avalon explosion, . This was after the Earth had thawed from the Cryogenian period's extensive glaciation. This biota largely disappeared with the rapid increase in biodiversity known as the Cambrian explosion. Most of the currently existing body plans of animals first appeared in the fossil record of the Cambrian rather than the Ediacaran. For macroorganisms, the Cambrian biota appears to have almost completely replaced the organisms that dominated the Ediacaran fossil record, although relationships are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran
The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and the beginning of the Phanerozoic Eon. It is named after the Ediacara Hills of South Australia. The Ediacaran Period's status as an official geological period was ratified in 2004 by the International Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years. Although the period takes its name from the Ediacara Hills where geologist Reg Sprigg first discovered fossils of the eponymous Ediacaran biota in 1946, the type section is located in the bed of the Enorama Creek within Brachina Gorge in the Flinders Ranges of South Australia, at . The Ediacaran marks the first appearance of widespread multicellular fauna following the end of Snowball Earth glaciation events, the so-called Ediacaran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wigwamiella
'' Pseudorhizostomites howchini'' is a enigmatic member of the Ediacaran Biota which was originally been thought to have been a jellyfish of some kind (Sepkoski, 2002). ''P. howchini'' is now though to either have been a pseudofossil, a gas escape structure or perhaps the result of a rangeomorph holdfast being pulled by currents or, if any of these possibilities are not true, some other force from the sediments which enclosed the fossil. Distribution and discovery Reginald Sprigg found the Holotype of ''P. howchini'' within the Flinders Ranges of South Australia. Fossils of ''Pseudorhizostomites'' also occur within the White Sea region of Russia on Zimnii Bereg, the Dniester River Basin of Podolia, Ukraine and Gornaya Baskkiria of the Ryauzyak Basin. These fossils are commonly found at all locations. Classification and interpretations Originally, Sepkoski (2002) suggested the possibility of the problematic fossils as being a Jellyfish. Although a more modern and updated i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elkanah Billings
Elkanah Billings (May 5, 1820 – June 14, 1876) is often referred to as Canada's first paleontologist. Billings was born on a farm by the Rideau River outside Bytown (Ottawa), now known as Billings Estate. His parents were named Lamira Dow and Braddish Billings. His family included an older sister named Sabra and an older brother Maj Braddish Billings Jr, who practised as an architect and served in the North-West Rebellion. His younger siblings were Samuel, Sarah (known as Sally) and Charles. He was originally educated in law and in 1845, he was called to the Canadian bar. In 1856, he founded the journal the ''Canadian Naturalist (and Geologist)''. He continued to practise law until 1857, when he was hired to be the first paleontologist for Geological Survey of Canada (GSC). In his lifetime, he identified 1065 new species and 61 new genera, including ''Aspidella'', the first documented fossil of the Ediacaran biota. He married Helen Walker Wilson in 1845. However, he was c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homonym
In linguistics, homonyms are words which are homographs (words that share the same spelling, regardless of pronunciation), or homophones (equivocal words, that share the same pronunciation, regardless of spelling), or both. Using this definition, the words ''row'' (propel with oars), ''row'' (a linear arrangement) and ''row'' (an argument) are homonyms because they are homographs (though only the first two are homophones): so are the words ''see'' (vision) and ''sea'' (body of water), because they are homophones (though not homographs). A more restrictive and technical definition requires that homonyms be simultaneously homographs ''and'' homophoneshomonym ''Random House Unabridged Dictionary'' at dictionary.com – that is to say they have identical spelling ''and'' pronunciation, but with different meanings. Examples are the pair ''stalk'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Doolittle Walcott
Charles Doolittle Walcott (March 31, 1850February 9, 1927) was an American paleontologist, administrator of the Smithsonian Institution from 1907 to 1927, and director of the United States Geological Survey.Wonderful Life (book) by Stephen Jay Gould published in 1989, Chapter 4 He is famous for his discovery in 1909 of well-preserved fossils, including some of the oldest soft-part imprints, in the Burgess Shale of British Columbia, Canada. Early life Charles Doolittle Walcott was born on March 31, 1850 in New York Mills, New York. His grandfather, Benjamin S. Walcott, moved from Rhode Island in 1822. His father, also Charles Doolittle Walcott, died when Charles Jr. was only two. Walcott was the youngest of four children. He was interested in nature from an early age, collecting minerals and bird eggs and, eventually, fossils. He attended various schools in the Utica area but left at the age of eighteen without completing high school, the end of his formal education. His intere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleontologist
Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossils to classify organisms and study their interactions with each other and their environments (their paleoecology). 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 (, "old, ancient"), (, ( gen. ), "being, creature"), and (, "speech, thought, study"). Paleontology lies on the border between biology and geology, but differs from archaeology in that it excludes the study of anatomically modern humans. It now uses techniques drawn from a wide range of sciences, including biochemistry, mathematics, and engineer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Survey Of Canada
The Geological Survey of Canada (GSC; french: Commission géologique du Canada (CGC)) is a Canadian federal government agency responsible for performing geological surveys of the country, developing Canada's natural resources and protecting the environment. A branch of the Earth Sciences Sector of Natural Resources Canada, the GSC is the country's oldest scientific agency and was one of its first government organizations. History In September 1841, the Province of Canada legislature passed a resolution that authorized the sum of £1,500 sterling be granted to the government for the estimated expense of performing a geological survey of the province. In 1842, the Geological Survey of Canada was formed to fulfill this request.Christy Vodden (1992)No Stone Unturned: The First 150 years of the Geological Survey of Canada Geological Survey of Canada Web site William Edmond Logan was in Montreal at the time and made it known that he was interested in participating in this survey. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
