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Rugoconites Tenuirugosus
''Rugoconites'' is a genus of Ediacaran biota found as fossils in the form of a circular or oval-like impression preserved in high relief, six or more centimeters in diameter. The fossils are surrounded by frills that have been interpreted ( Wade 1972) as sets of tentacles. The bifurcating radial ribs, spreading from a central dome, serve to distinguish this genus from the sponge ''Palaeophragmodictya'', and may represent the channels of the gastrovascular system. Fossils of ''Rugoconites'' have been interpreted as early sponges, although this is countered by Sepkoski ''et al.'' (2002), who interpreted the organism as a free-swimming jellyfish-like cnidarian; similar to '' Ovatoscutum''. However, the fossil is consistently preserved as a neat circular form and its general morphology does not vary, therefore a benthic and perhaps slow-moving or sessile lifestyle is more likely. Ivantstov & Fedonkin (2002), suggest that ''Rugoconites'' may possess tri-radial symmetry and be a memb ... [...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 biota, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastrovascular Cavity
The gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Coelenterates or cnidarians (including jellyfish and corals) and Platyhelminthes (flatworms). The cavity may be extensively branched into a system of canals. In cnidarians, the gastrovascular system is also known as the coelenteron, and is commonly known as a "blind gut" or "blind sac", since food enters and waste exits through the same orifice. The radially symmetrical cnidarians have a sac-like body in two distinct layers, the epidermis and gastrodermis, with a jellylike layer called the mesoglea between. Extracellular digestion takes place within the central cavity of the sac-like body. This cavity has only one opening to the outside which, in most cnidarians, is surrounded by tentacle In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Described In 1992
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes in zoological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Described In 1966
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes in zoological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bulletins Of American Paleontology
''Bulletins of American Paleontology'' is a peer-reviewed scientific journal published by the Paleontological Research Institution and issued biannually that features monographs and dissertations in the field of paleontology and other related subjects. Founded by Gilbert Harris in 1895, it is the oldest continuously-published paleontological periodical in the Western Hemisphere, and one of the oldest in the world. History In 1895, Gilbert Harris, a professor of geology at Cornell University, established ''Bulletins of American Paleontology'' in order to publish his research on Paleocene and Eocene mollusk fossils. Printing originally took place at Harris's own printing enterprise at McGraw Hall, Cornell. Publication of ''Bulletins'' was transferred to the Paleontological Research Institution The Paleontological Research Institution, or PRI, is a paleontological organization in Ithaca, New York, with a mission including both research and education. PRI is affiliated with Cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Ediacaran Genera ...
This is a list of all described Ediacaran genera, including the Ediacaran biota. It contains 227 genera. References {{reflist, 30em * 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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mary Wade
Mary Wade (17 December 1775 – 17 December 1859) was a British woman and convict who was transported to Australia when she was 13 years old. She was the youngest convict aboard , part of the Second Fleet. Her family grew to include five generations and over 300 descendants in her own lifetime. Early years in London Researchers in the 1980s believed that Wade was born on 5 October 1777 at Southwark, London, to Mary English and George Wade, and was christened on 21 December 1777 at Saint Olave, Southwark, Surrey, England however, a later group of researchers, with access to records not previously available, now believe that Wade was born on 17 December 1775, in the parish of Westminster St Margaret and St John, Middlesex, to Lawrence Wade (died August 1794, Perkins Rents, Westminster) and Mary Smith (died November 1836, 5 New Court, Westminster), and was baptised on 7 January 1776, at St Margaret's, Westminster. Evidence for her revised date of birth and parents inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taphonomy
Taphonomy is the study of how organisms decay and become fossilized or preserved in the paleontological record. The term ''taphonomy'' (from Greek , 'burial' and , 'law') was introduced to paleontology in 1940 by Soviet scientist Ivan Efremov to describe the study of the transition of remains, parts, or products of organisms from the biosphere to the lithosphere. The term taphomorph is used to describe fossil structures that represent poorly-preserved, deteriorated remains of a mixture of taxonomic groups, rather than of a single one. Description Taphonomic phenomena are grouped into two phases: biostratinomy, events that occur between death of the organism and the burial; and diagenesis, events that occur after the burial. Since Efremov's definition, taphonomy has expanded to include the fossilization of organic and inorganic materials through both cultural and environmental influences. This is a multidisciplinary concept and is used in slightly different contexts throughout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobozoa
''Trilobozoa'' (meaning "three-lobed animals") is a phylum of extinct mobile animals that were originally classified into the Cnidaria. The basic body plan of ''Trilobozoa'' is often a tri-radial or radial sphere-shaped form with lobes radiating from its centre. Fossils of trilobozoans are restricted to marine strata of the Late Ediacaran period. History and interpretations Originally, both Fedonkin and Runnegar presumed that there were 2-3 families within the Trilobozoa, those families being Albumaresidae Fedonkin, 1985 and Tribrachididae Runnegar, 1992. Although, affinities with the Conulariida were made because of the conulariids possessing similar three-fold symmetry. Mikhail Fedonkin later classified the Trilobozoa as a class of the Phylum Coelenterata. Most of the members of what is now the modern day classification for Trilobozoa were thought to have originally been free swimming Jellyfish. Tribrachidium was once interpreted as a Edrioasteroid Echinoderm, although wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symmetry In Biology
Symmetry in biology refers to the symmetry observed in organisms, including plants, animals, fungi, and bacteria. External symmetry can be easily seen by just looking at an organism. For example, take the face of a human being which has a plane of symmetry down its centre, or a pine cone with a clear symmetrical spiral pattern. Internal features can also show symmetry, for example the tubes in the human body (responsible for transporting gases, nutrients, and waste products) which are cylindrical and have several planes of symmetry. Biological symmetry can be thought of as a balanced distribution of duplicate body parts or shapes within the body of an organism. Importantly, unlike in mathematics, symmetry in biology is always approximate. For example, plant leaves – while considered symmetrical – rarely match up exactly when folded in half. Symmetry is one class of patterns in nature whereby there is near-repetition of the pattern element, either by reflection or rotation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mikhail Fedonkin
Academician Mikhail Aleksandrovich Fedonkin (russian: Михаи́л Алекса́ндрович Федо́нкин; born June 19, 1946) is a Russian paleontologist specializing in documentation of the earliest animals' body fossils, tracks, and trails. He has also described numerous Vendian-aged fossils including '' Hiemalora'', ''Cephalonega'', and '' Nimbia occlusa''. Early life Fedonkin was born in Orekhovo-Zuevo, Moscow Region, Russia. In 1969, Fedonkin presented a thesis titled "Biostratigraphy and paleontology of the Late Precambrian deposits of Kharaulakh Mountains, Northern Yakutia (Sakha)" to earn his MSc in Geology from Moscow State University. He went on to obtain a PhD in Stratigraphy\Paleontology (1978) and a Doctorate of Science in Paleobiology (1985) from the Geological Institute, USSR Academy of Sciences, Moscow for his dissertations on "Precambrian fauna and trace fossils from the Russian Platform north" and "Non-skeletal fauna of the Vendian and its pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ovatoscutum
''Ovatoscutum concentricum'' is one of many enigmatic organisms known from the Ediacaran deposits of the Flinders Ranges, Australia, and the White Sea area in Russia, dating around 555 Ma. Etymology The generic name ''Ovatoscutum'' is derived from the Latin ''ovatus'' (oval) and ''scutum'' (shield). Description This fossil has the form of a rounded shield, enclosing strongly concentric corrugations or ribs, which weaken adjacent to a triangular neckline. A suture-like zone extends through the center from the apex of the neckline towards the opposite margin. The ribs become wider towards the periphery. The symmetry of these ribs exhibits glide reflection (opposite isometry); that is, the corresponding segments on the left and right sides do not line up, but are offset. Affinity ''Ovatoscutum'' was first described by Martin Glaessner and Mary Wade in 1966, and this team tentatively interpreted it as a chondrophoran pneumatophore. This notion was based on morphologies apparently ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
