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Tribrachidium
''Tribrachidium heraldicum'' is a tri-radially symmetric fossil animal that lived in the late Ediacaran (Vendian) seas. In life, it was hemispherical in form. ''T. heraldicum'' is the best known member of the extinct group Trilobozoa. Etymology The generic name ''Tribrachidium'' is derived from combination of the grc, τρία (, "three") + la, brachium ("arm") + diminutive suffix . The specific name ''T. heraldicum'' references the similarity of the pattern of this fossil with the well-known heraldic triskelion design, such as the coat of arms of the Isle of Man. Occurrence ''Tribrachidium'' fossils were first discovered in the Ediacara Member of the Rawnslay Quartzite, Flinders Ranges in South Australia. This fossil is also known from the Mogilev Formation in the Dniester River Basin, Podolia, Ukraine and from the Verkhovka, Zimnegory and Yorga Formations in the White Sea area of the Arkhangelsk Region, Russia. Description ''T. heraldicum'' is preserved as negative impressio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gehlingia
''Gehlingia dibrachida'' is a species of enigmatic Ediacaran organism from South Australia described in 1998. ''Gehlingia'' has been described as having many characteristics of petalonamids, although it has been classified as a rather close relative of the ''Tribrachidium''. The overall shape of ''Gehlingia'' contradicts this affinity, however, with its shape being a more Bilaterally symmetrical one although the basic structure similar to that of Tribrachidium appears in ''Gehlingia'' as separate branches extending into bifurcating minor branches along with "thumb structures" that are apparent in Tribrachidium in the form of side bulges on an axis. Etymology The name of the genus, "Gehlingia", is in honour of the Australian palaeontologist specialising in Ediacaran fossils, James G. Gehling. Description ''Gehlingia dibrachida'' represents a frond-like bilaterally symmetric organism with two fronds with each half of them having a swollen axis on an inner edge. The organism's ... [...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 Mikhail A. Fedonkin, 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 (biology), 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triskelion
A triskelion or triskeles is an ancient motif consisting of a triple spiral exhibiting rotational symmetry. The spiral design can be based on interlocking Archimedean spirals, or represent three bent human legs. It is found in artefacts of the European Neolithic and Bronze Age with continuation into the Iron Age especially in the context of the La Tène culture and related Celtic traditions. The actual ''triskeles'' symbol of three human legs is found especially in Greek antiquity, beginning in archaic pottery and continued in coinage of the classical period. In the Hellenistic period, the symbol becomes associated with the island of Sicily, appearing on coins minted under Dionysius I of Syracuse beginning in BCE. It later appears in heraldry, and, other than in the flag of Sicily, came to be used in the flag of the Isle of Man (known as ''ny tree cassyn'' "the three legs"). Greek (''triskelḗs'') means "three-legged". While the Greek adjective "three-legged .g. of ... [...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 rotat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anfesta
''Anfesta stankovskii'' is a tri-radially symmetrical fossil animal that lived in the late Ediacaran (Vendian) seafloor. It is a member of the extinct group Trilobozoa. Etymology The generic and specific names of the ''Anfesta stankovskii'' honour the Arkhangel'sk geologist Anatoliy F. Stankovskii. Occurrence Fossils of ''Anfesta stankovskii'' are known from deposits of the Verkhovka and Yorga formations on the Karakhta River in Onega Peninsula and Zimnii Bereg (Winter Coast) of the White Sea, Arkhangelsk Region, Russia. Description ''Anfesta'' represents a flattened, hemispherical form with three-fold symmetry. At the centre of the organism, 3 elongate and sausage-like ridges radiate from the centre and are put away from each other by 120 degrees and make the animal always divisible into 3 parts and the ridges becoming rounded at both edges. The same ridges bifurcate twice near both of their ends. In some specimens of ''A. stankovskii'', a large amount of furrows (originall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albumares
''Albumares brunsae'' is a tri-radially symmetrical fossil animal that lived in the late Ediacaran seafloor. It is a member of the extinct group Trilobozoa. Etymology The generic name ''Albumares'' derives from the Latin ''Mare Album'' (White Sea). The specific name honors Elizabeth P. Bruns, an early 20th-century Russian geologist noted for her extensive and important research of the Upper Precambrian stratigraphy of European Russia. Occurrence Fossils of the ''Albumares brunsae'' are known from deposits on the Verkhovka formation on the Syuzma River in the Onega Peninsula of the White Sea, Arkhangelsk Region, Russia. There are reports about ''Albumares'' sp. from the Rawnslay Quartzite, Flinders Ranges in the South Australia, but photographs or description of these fossils have not yet been published. Description ''Albumares'' fossils are preserved as negative, low impressions on the bases of sandstone beds. The fossil exhibits circular, trefoil-like (three-lobe) form, and ... [...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] |
Podolia
Podolia or Podilia ( uk, Поділля, Podillia, ; russian: Подолье, Podolye; ro, Podolia; pl, Podole; german: Podolien; be, Падолле, Padollie; lt, Podolė), is a historic region in Eastern Europe, located in the west-central and south-western parts of Ukraine and in northeastern Moldova (i.e. northern Transnistria). The name derives from Old Slavic ''po'', meaning "by/next to/along" and ''dol'', "valley" (see dale). Geography The area is part of the vast East European Plain, confined by the Dniester River and the Carpathian arc in the southwest. It comprises an area of about , extending for from northwest to southeast on the left bank of the Dniester. In the same direction run two ranges of relatively low hills separated by the Southern Bug, ramifications of the Avratynsk heights. The Podolian Upland, an elongated, up to high plateau stretches from the Western and Southern Bug rivers to the Dniester, and includes hill countries and mountainous regions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flinders Ranges
The Flinders Ranges are the largest mountain range in South Australia, which starts about north of Adelaide. The ranges stretch for over from Port Pirie to Lake Callabonna. The Adnyamathanha people are the Aboriginal group who have inhabited the range for tens of thousands of years. Its most well-known landmark is Wilpena Pound / Ikara, a formation that creates a natural amphitheatre covering and containing the range's highest peak, St Mary Peak (). The ranges include several national parks, the largest being the Ikara-Flinders Ranges National Park, as well as other protected areas. It is an area of great geological and palaeontological significance, and includes the oldest fossil evidence of animal life was discovered. The Ediacaran Period and Ediacaran biota take their name from the Ediacara Hills within the ranges. In August 2022, a nomination for the Flinders Ranges to be named a World Heritage Site was lodged. History The first humans to inhabit the Flinders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microbial Mats
A microbial mat is a multi-layered sheet of microorganisms, mainly bacteria and archaea, or bacteria alone. Microbial mats grow at interfaces between different types of material, mostly on submerged or moist surfaces, but a few survive in deserts. A few are found as endosymbionts of animals. Although only a few centimetres thick at most, microbial mats create a wide range of internal chemical environments, and hence generally consist of layers of microorganisms that can feed on or at least tolerate the dominant chemicals at their level and which are usually of closely related species. In moist conditions mats are usually held together by slimy substances secreted by the microorganisms. In many cases some of the bacteria form tangled webs of filaments which make the mat tougher. The best known physical forms are flat mats and stubby pillars called stromatolites, but there are also spherical forms. Microbial mats are the earliest form of life on Earth for which there is good fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
