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Octocorallia Genera
Octocorallia, along with Hexacorallia, is one of the two extant classes of Anthozoa. It comprises over 3,000 species of marine and brackish animals consisting of colonial polyps with 8-fold symmetry, commonly referred informally as "soft corals". It was previously known by the now unaccepted scientific names Alcyonacea and Gorgonacea, both deprecated , and by the also deprecated name of Alcyonaria, in earlier times. Its only two orders are Malacalcyonacea and Scleralcyonacea, which include corals such as those under the common names of blue corals, sea pens, and gorgonians (sea fans and sea whips). These animals have an internal skeleton secreted by their mesoglea, and polyps with tipically eight tentacles and eight mesenteries. As is the case with all cnidarians, their complex life cycle includes a motile, planktonic phase (a larva called planula), and a later characteristic sessile phase. Octocorals have existed at least since the Ordovician period, as shown b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendronephthya Klunzingeri
''Dendronephthya klunzingeri'' is a species of soft coral in the family Nephtheidae. This species is divaricate Divaricate means branching, or having separation or a degree of separation. The angle between branches is wide. In botany In botany, the term is often used to describe the branching pattern of plants. Plants are said to be divaricating when th ... with discontinuous contours. Each bundle has 10 to 12 polyps. The branching lobes have sizable bunches. References Animals described in 1888 Nephtheidae {{octocorallia-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesentery (zoology)
In zoology, a mesentery is a membrane inside the body cavity of an animal. The term identifies different structures in different phylum, phyla: in vertebrates it is a double fold of the peritoneum enclosing the intestines; in other organisms it forms complete or incomplete partitions of the body cavity, whether that is the coelom or, as in the Anthozoa, the gastrovascular cavity. The word "mesentery" is derived from the Greek ''mesos'', "in the middle" and ''enteron'', an "intestine". Vertebrates In vertebrates, a mesentery is a membrane consisting of a double fold of peritoneum that encloses the intestines and their associated organs and connect them with the dorsal wall of the abdominal cavity. In invertebrates, a mesentery is a support or partition in a body cavity serving a similar function to the mesenteries of vertebrates. Bilateria In Bilateria, bilaterally symmetrical organisms, there is often a major mesentery separating the two halves of the coelom. In segmented org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Techniques
Molecular biology is a branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. Though cells and other microscopic structures had been observed in living organisms as early as the 18th century, a detailed understanding of the mechanisms and interactions governing their behavior did not emerge until the 20th century, when technologies used in physics and chemistry had advanced sufficiently to permit their application in the biological sciences. The term 'molecular biology' was first used in 1945 by the English physicist William Astbury, who described it as an approach focused on discerning the underpinnings of biological phenomena—i.e. uncovering the physical and chemical structures and properties of biological molecules, as well as their interactions with other molecules and how these interactions explain observations of so-called classical biology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian
The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovician Period 486.85 Ma. Most of the continents lay in the southern hemisphere surrounded by the vast Panthalassa Ocean. The assembly of Gondwana during the Ediacaran and early Cambrian led to the development of new convergent plate boundaries and continental-margin arc magmatism along its margins that helped drive up global temperatures. Laurentia lay across the equator, separated from Gondwana by the opening Iapetus Ocean. The Cambrian marked a profound change in life on Earth; prior to the Period, the majority of living organisms were small, unicellular and poorly preserved. Complex, multicellular organisms gradually became more common during the Ediacaran, but it was not until the Cambrian that fossil diversity seems to rapidly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pywackia
''Pywackia'' is a contentious Cambrian fossil that has been interpreted as the earliest (total group) Bryozoan, and the only representative of that phylum in the Cambrian period. Its Bryozoan credentials have been called into question, but the octocoral alternative is equally unconvincing, and there are reasons to suggest a position in the Stenolaemata Stenolaemata are a class of exclusively marine bryozoans. Stenolaemates originated and diversified in the Ordovician, and more than 600 species are still alive today.Fossils of Mexico [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of '' Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before prin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GFF (journal)
GFF may refer to: Entertainment * Girlfriends Films, an American pornographic studio * Glasgow Film Festival, in Scotland * Gothenburg Film Festival, in Sweden Sports * Gabonese Football Federation * Gambia Football Federation * Georgian Football Federation * Göteborgs FF, Swedish football club * Gothenburg Football Association * Guinean Football Federation * Guyana Football Federation Other uses * ''GFF'' (journal), a geology journal * General feature format, a file format used for describing genes * Gesellschaft für Freiheitsrechte (Society for Civil Rights), a Berlin-based non-profit organization * Göteborgs FyrverkeriFabrik, a Swedish fireworks company * Griffith Airport, in New South Wales, Australia * Griffith railway station Griffith railway station is located on the Yanco–Griffith line in New South Wales, Australia. It serves the city of Griffith. History Griffith station opened on 3 July 1916 when the Temora-Roto line was extended from Barellan. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maurits Lindström
Maurits Lindström (10 May 1932 – 14 November 2009) was a Swedish geologist and paleontologist. Lindström's initial work was divided among two topics conodont paleontology and the structural geology of the Scandinavian Caledonides in Lappland. In 1970, he described the conodont families Cordylodontidae, Gondolellidae, Proconodontidae and Rhipidognathidae. In 1971, he described the conodont genera '' Baltoniodus'', '' Microzarkodina'' and '' Paracordylodus''.Vom Anfang, Hochstand und Ende eines Epikontinentalmeeres. Maurits Lindström, Geologische Rundschau, March 1971, Volume 60, Issue 2, pages 419-438, Lindström published conodont studies up to 1987 after which he only supervised students working with conodonts. In the late 1980s Lindström began to study ancient impact craters in the Fennoscandian Shield. His studies have confirmed earlier speculations that Tvären and Lockne are craters. Awards and tributes In 1985 he became member of the Royal Swedish Academ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordovician
The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years from the end of the Cambrian Period Megaannum, Ma (million years ago) to the start of the Silurian Period Ma. The Ordovician, named after the Celtic Britons, Welsh tribe of the Ordovices, was defined by Charles Lapworth in 1879 to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, who were placing the same Rock (geology), rock beds in North Wales in the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed Stratum, strata were different from those of either the Cambrian or the Silurian systems, and placed them in a system of their own. The Ordovician received international approval in 1960 (forty years after Lapworth's death), when it was adopted as an official per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sessility (zoology)
Sessility is the biological property of an animal describing its lack of a means of self-locomotion. Sessile animals for which natural ''motility'' is absent are normally immobile. This is distinct from the botanical concept of sessility, which refers to an organism or biological structure attached directly by its base without a stalk. Sessile animals can move via external forces (such as water currents), but are usually permanently attached to something. Organisms such as corals lay down their own substrate from which they grow. Other organisms grow from a solid object, such as a rock, a dead tree trunk, or a human-made object such as a buoy or ship's hull. Mobility Sessile animals typically have a motile phase in their development. Sponges have a motile larval stage and become sessile at maturity. Conversely, many jellyfish develop as sessile polyps early in their life cycle. In the case of the cochineal, it is in the nymph stage (also called the crawler stage) that the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planula
A planula is the free-swimming, flattened, ciliated, bilaterally symmetric larval form of various cnidarian species and also in some species of Ctenophores, which are not related to cnidarians at all. Some groups of Nemerteans also produce larvae that are very similar to the planula, which are called planuliform larva. In a few cnidarian clades, like Aplanulata and the parasitic Myxozoa, the planula larval stage has been lost. Development The planula forms either from the fertilized egg of a medusa, as is the case in scyphozoans and some hydrozoans, or from a polyp, as in the case of anthozoans. Depending on the species, the planula either metamorphoses directly into a free-swimming, miniature version of the mobile adult form, or navigates through the water until it reaches a hard substrate (many may prefer specific substrates) where it anchors and grows into a polyp. The miniature-adult types include many open-ocean scyphozoans. The attaching types include all anthozoans w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase of their life cycle. A larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. In the case of smaller primitive arachnids, the larval stage differs by having three instead of four pairs of legs. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
