|
Choiaella
''Choiaella'' is an extinct genus of sea sponge ranging from the Chengjiang lagerstatten until the Lower Silurian. It is closely related to the genera ''Choia'' and '' Allantospongia'', which the Chengjiang fauna species ''C. radiata'' coexisted sympatrically with. The species ''C. scotica'' is known from the Caradoc-aged fine sandstone of Wallace's Cast, Southern Uplands of Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the .... The Silurian species has not been formally named. References Maotianshan shales fossils Protomonaxonida Silurian extinctions Cambrian first appearances Prehistoric sponge genera Fossil taxa described in 1995 {{silurian-animal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protomonaxonida
Protomonaxonida is an extinct order of sea sponges. It is a paraphyletic group gathering the most ancient species from the Burgess Shale to modern sponges. Families and genera * Family † Choiidae Laubenfels, 1925 ** Genus †'' Allantospongia'' Rigby & Hou, 1995 ** Genus †''Choia'' Walcott, 1920 ** Genus †'' Choiaella'' Rigby & Hou, 1995 ** Genus †'' Lenica'' Goryanskiy, 1977 * Family † Halichondritidae Rigby, 1986 ** Genus †'' Halichondrites'' Walcott, 1920 ** Genus †'' Pohlispongia'' Rigby & von Bitter, 2005 * Family † Hamptoniidae De Laubenfels, 1955 ** Genus †'' Hamptonia'' Walcott, 1920 ** Genus †'' Hamptoniella'' Rigby & Collins, 2004 * Family † Hazeliidae De Laubenfels, 1955 ** Genus †'' Crumillospongia'' Rigby, 1986 ** Genus †'' Falospongia'' Rigby, 1986 ** Genus †'' Hazelia'' Walcott, 1920 * Family † Leptomitidae De Laubenfels, 1955 ** Genus †'' Leptomitus'' Walcott, 1886 ** Genus †'' Paraleptomitella'' Chen et al., 1989 ** Genus † ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Paleontology
The ''Journal of Paleontology'' is a peer-reviewed scientific journal covering the field of paleontology. It is published by the Paleontological Society. Indexing The ''Journal of Paleontology'' is indexed in: *BIOSIS Previews *Science Citation Index *The Zoological Record *GeoRef __NOTOC__ The GeoRef database is a bibliographic database that indexes scientific literature in the geosciences, including geology. Coverage ranges from 1666 to the present for North American literature, and 1933 to the present for the rest of t ... References Paleontology journals Publications established in 1927 Academic journals published by learned and professional societies Cambridge University Press academic journals Bimonthly journals Paleontological Society {{paleo-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Sponge
Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells. Sponges have unspecialized cells that can transform into other types and that often migrate between the main cell layers and the mesohyl in the process. Sponges do not have nervous, digestive or circulatory systems. Instead, most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes. Sponges were first to branch off the evolutionary tree from the last common ancestor of all animals, making them the sister group of all other animals. Etymology The term ''sponge'' derives from the Ancient Greek word ( 'sponge'). Overview Sponges are similar to other animals in that they are multicellular, he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chengjiang
Chengjiang (; earlier Tchinkiang) is a city located in Yuxi, Yunnan Province, China, just north of Fuxian Lake. Administrative divisions Chengjiang City has 2 subdistricts and 4 townships. ;2 subdistricts * Fenglu () * Longjie () ;4 towns Chengjiang Fossil Site In evolutionary biology, and especially paleontology, Chengjiang is noted for soft-tissue fossil finds, of the Maotianshan Shales, dated less than 518 million years ago during the Cambrian explosion, which "are as spectacular as the Burgess Shale fauna, and significantly older." Also These fossils are considered one of the most important fossil finds of the 20th century. They contain an exquisite degree of detail, cover a diverse range of fauna, and are significant in attempts to understand the evolution of life on Earth. In 2012, the Changjiang Fossil Site became a UNESCO World Heritage Site. The fossils were first discovered by Henri Mansuy and Jaques Deprat who described them in 1912, the year after Charles Walc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geobios
Geobios is an academic journal published bimonthly by the publishing house Elsevier. Geobios is an international journal of paleontology, focusing on the areas of palaeobiology, palaeoecology, palaeobiogeography, stratigraphy and biogeochemistry Biogeochemistry is the scientific discipline that involves the study of the chemical, physical, geological, and biological processes and reactions that govern the composition of the natural environment (including the biosphere, the cryosphere, t .... Geobios is indexed and abstracted in: Science Citation Index, ISI, Bulletin signalétique, PASCAL, Geo Abstracts, Biological Abstracts, The Geoscience Database, Referativnyi Zhurnal, SciSearch, Research Alert and Current Contents/Physical, Chemical & Earth Sciences. Description Articles are published only in English, following a standard peer-review process (usually involving 3 reviewers) supervised by an associate-editor through the Journal's submission web site. Articles are published i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choia
''Choia'' is a genus of extinct demosponge ranging from the Cambrian until the Lower Ordovician periods. Fossils of ''Choia'' have been found in the Burgess Shale in British Columbia; the Maotianshan shales of China; the Wheeler Shale in Utah; and the Lower Ordovician Fezouata formation. It was first described in 1920 by Charles Doolittle Walcott. Life habit ''Choia'' was originally thought to be not attached to the sea bed: the living animal was originally thought to rest directly on the substrate, with the radiating spines from the edge of its flattish, conical body, giving an appearance not unlike that of the peak of a big top, with guy lines. Recently discovered fossils from Lower Ordovician Morocco show that the living animal was actually suspended high above the seafloor, attached via stalk-like spines derived from spicules. Water is assumed to have entered the sponge parallel to the spines, being expelled, presumably, from a central opening. Species reached up to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sympatric
In biology, two related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter one another. An initially interbreeding population that splits into two or more distinct species sharing a common range exemplifies sympatric speciation. Such speciation may be a product of reproductive isolation – which prevents hybrid offspring from being viable or able to reproduce, thereby reducing gene flow – that results in genetic divergence. Sympatric speciation may, but need not, arise through secondary contact, which refers to speciation or divergence in allopatry followed by range expansions leading to an area of sympatry. Sympatric species or taxa in secondary contact may or may not interbreed. Types of populations Four main types of population pairs exist in nature. Sympatric populations (or species) contrast with parapatric populations, which contact one another in adjacent but not shared ranges and do no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caradoc
Caradoc Vreichvras (; Modern cy, Caradog Freichfras, ) was a semi-legendary ancestor to the kings of Gwent. He may have lived during the 5th or 6th century. He is remembered in the Matter of Britain as a Knight of the Round Table, under the names King Carados and Carados Briefbras (French for "Carados Shortarm"). Identification and historicity Though the name "Caradoc" and its various forms were by no means uncommon during the Middle Ages, it is probable some of the Caradocs referred to in Welsh genealogies and hagiographies such the ''Life of St. Tatheus'' are the same person. Due to the name's prevalence considerable confusion exists about Caradoc's identity, both historical and literary. He may have become confused with the British hero Caratacus (the Latin form of Caradoc), Cerdic of Wessex and any number of British history's later Caradocs. His parentage varies from text to text; he is called the son of Llŷr Marini (possibly implying Llŷr) several times in the '' Mabin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scotland
Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the north and west, the North Sea to the northeast and east, and the Irish Sea to the south. It also contains more than 790 islands, principally in the archipelagos of the Hebrides and the Northern Isles. Most of the population, including the capital Edinburgh, is concentrated in the Central Belt—the plain between the Scottish Highlands and the Southern Uplands—in the Scottish Lowlands. Scotland is divided into 32 administrative subdivisions or local authorities, known as council areas. Glasgow City is the largest council area in terms of population, with Highland being the largest in terms of area. Limited self-governing power, covering matters such as education, social services and roads and transportation, is devolved from the Scott ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silurian Extinctions
The Silurian ( ) is a period (geology), geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago (annum, Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoic Era (geology), Era. As with other geologic periods, the Rock (geology), rock beds that define the period's start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out. One important event in this period was the initial establishment of terrestrial life in what is known as the Silurian-Devonian Terrestrial Revolution: vascular plants emerged from more primitive land plants, dikaryan fungi started expanding and diversifying along with glomeromycotan fungi, and three groups of arthropods (myriapods, arachnids and Hexapoda, hexapods) became fully t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
