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Balanus Glandula
''Balanus glandula'' (North American Acorn Barnacle, Common Acorn Barnacle) is one of the most common barnacle species on the Pacific coast of North America, distributed from the U.S. state of Alaska to Bahía de San Quintín near San Quintín, Baja California. They are commonly found in the upper intertidal zone on mussels, rocks and pier pilings. They can obtain oxygen from both water and air. This acorn barnacle is a moderate-sized one with a diameter of up to . The shell is formed by overlapping plates and has a calcareous basis. It has more the shape of a cylinder than the shape of a cone. The white operculum has heavily ridged walls. It can live up to ten years. It has been intensely studied in recent years as a model species for linking physical oceanography and population genetics (or phylogeography) surveys. This species was introduced to the shores of Argentina in the 1960s, and has become an invasive species An invasive species otherwise known as an alien is an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chthamalus Fissus
''Chthamalus fissus'' is a species of star barnacle in the family Chthamalidae The Chthamalidae are a family of chthamaloid barnacles, living entirely in intertidal/subtidal habitats, characterized by a primary shell wall of eight, six, or four plates, lacking imbricating plate whorls, and either membraneous or more rare .... References External links * Sessilia {{crustacean-stub Crustaceans described in 1854 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (gastropod)
The operculum (; ) is a corneous or calcareous anatomical structure like a trapdoor that exists in many (but not all) groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc. The operculum is attached to the upper surface of the foot and in its most complete state, it serves as a sort of "trapdoor" to close the aperture of the shell when the soft parts of the animal are retracted. The shape of the operculum varies greatly from one family of gastropods to another. It is fairly often circular, or more or less oval in shape. In species where the operculum fits snugly, its outline corresponds exactly to the shape of the aperture of the shell and it serves to seal the entrance of the shell. Many families have opercula that are reduced in size, and which a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustaceans Of The Eastern Pacific Ocean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans (Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barnacles
A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile (nonmobile) and most are suspension feeders, but those in infraclass Rhizocephala are highly specialized parasites on crustaceans. They have four nektonic (active swimming) larval stages. Around 1,000 barnacle species are currently known. The name is Latin, meaning "curl-footed". The study of barnacles is called cirripedology. Description Barnacles are encrusters, attaching themselves temporarily to a hard substrate or a symbiont such as a whale ( whale barnacles), a sea snake ('' Platylepas ophiophila''), or another crustacean, like a crab or a lobster (Rhizocephala). The most common among them, "acorn barnacles" ( Sessilia), are sessile where they grow their shells directly onto the substrate. Pedunculate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The Marine Biological Association Of The United Kingdom
The ''Journal of the Marine Biological Association of the United Kingdom'' is a peer-reviewed scientific journal that was established in August 1887. Originally set up to provide members of the Marine Biological Association of the United Kingdom with "notes and reports concerning the work of the Association" along with "brief records of observations relating to the marine biology and fisheries of the coasts of the United Kingdom". Since 1937 the journal has been published by Cambridge University Press on behalf of the association. According to the ''Journal Citation Reports'', the journal has a 2017 impact factor of 1.403. References External links * volumes 1-11at Biodiversity Heritage Library The Biodiversity Heritage Library (BHL) is the world’s largest open access digital library for biodiversity literature and archives. BHL operates as worldwide consortiumof natural history, botanical, research, and national libraries working toge ... Academic journals associated with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invasive Species
An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native species that become harmful to their native environment after human alterations to its food webfor example the purple sea urchin (''Strongylocentrotus purpuratus'') which has decimated kelp forests along the northern California coast due to overharvesting of its natural predator, the California sea otter (''Enhydra lutris''). Since the 20th century, invasive species have become a serious economic, social, and environmental threat. Invasion of long-established ecosystems by organisms is a natural phenomenon, but human-facilitated introductions have greatly increased the rate, scale, and geographic range of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, the fourth-largest country in the Americas, and the eighth-largest country in the world. It shares the bulk of the Southern Cone with Chile to the west, and is also bordered by Bolivia and Paraguay to the north, Brazil to the northeast, Uruguay and the South Atlantic Ocean to the east, and the Drake Passage to the south. Argentina is a federal state subdivided into twenty-three provinces, and one autonomous city, which is the federal capital and largest city of the nation, Buenos Aires. The provinces and the capital have their own constitutions, but exist under a federal system. Argentina claims sovereignty over the Falkland Islands, South Georgia and the South Sandwich Islands, and a part of Antarctica. The earliest recorded human prese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Ecology
Molecular ecology is a field of evolutionary biology that is concerned with applying molecular population genetics, molecular phylogenetics, and more recently genomics to traditional ecological questions (e.g., species diagnosis, conservation and assessment of biodiversity, species-area relationships, and many questions in behavioral ecology). It is virtually synonymous with the field of "Ecological Genetics" as pioneered by Theodosius Dobzhansky, E. B. Ford, Godfrey M. Hewitt, and others. These fields are united in their attempt to study genetic-based questions "out in the field" as opposed to the laboratory. Molecular ecology is related to the field of conservation genetics. Methods frequently include using microsatellites to determine gene flow and hybridization between populations. The development of molecular ecology is also closely related to the use of DNA microarrays, which allows for the simultaneous analysis of the expression of thousands of different genes. Quanti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogeography
Phylogeography is the study of the historical processes that may be responsible for the past to present geographic distributions of genealogical lineages. This is accomplished by considering the geographic distribution of individuals in light of genetics, particularly population genetics. This term was introduced to describe geographically structured genetic signals within and among species. An explicit focus on a species' biogeography/biogeographical past sets phylogeography apart from classical population genetics and phylogenetics. Past events that can be inferred include population expansion, population bottlenecks, vicariance, dispersal, and migration. Recently developed approaches integrating coalescent theory or the genealogical history of alleles and distributional information can more accurately address the relative roles of these different historical forces in shaping current patterns. Development The term phylogeography was first used by John Avise in his 1987 work '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Genetics
Population genetics is a subfield of genetics that deals with genetic differences within and between populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as adaptation, speciation, and population structure. Population genetics was a vital ingredient in the emergence of the modern evolutionary synthesis. Its primary founders were Sewall Wright, J. B. S. Haldane and Ronald Fisher, who also laid the foundations for the related discipline of quantitative genetics. Traditionally a highly mathematical discipline, modern population genetics encompasses theoretical, laboratory, and field work. Population genetic models are used both for statistical inference from DNA sequence data and for proof/disproof of concept. What sets population genetics apart from newer, more phenotypic approaches to modelling evolution, such as evolutionary game theory and adaptive dynamics, is its emphasis on such genetic phenomena as dominance, epi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Oceanography
Physical oceanography is the study of physical conditions and physical processes within the ocean, especially the motions and physical properties of ocean waters. Physical oceanography is one of several sub-domains into which oceanography is divided. Others include biological, chemical and geological oceanography. Physical oceanography may be subdivided into ''descriptive'' and ''dynamical'' physical oceanography. Descriptive physical oceanography seeks to research the ocean through observations and complex numerical models, which describe the fluid motions as precisely as possible. Dynamical physical oceanography focuses primarily upon the processes that govern the motion of fluids with emphasis upon theoretical research and numerical models. These are part of the large field of Geophysical Fluid Dynamics (GFD) that is shared together with meteorology. GFD is a sub field of Fluid dynamics describing flows occurring on spatial and temporal scales that are greatly influenced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encyclopedia Of Life
The ''Encyclopedia of Life'' (''EOL'') is a free, online encyclopedia intended to document all of the 1.9 million living species known to science. It is compiled from existing trusted databases curated by experts and with the assistance of non-experts throughout the world. It aims to build one "infinitely expandable" page for each species, including video, sound, images, graphics, as well as text. In addition, the Encyclopedia incorporates content from the Biodiversity Heritage Library, which digitizes millions of pages of printed literature from the world's major natural history libraries. The project was initially backed by a US$50 million funding commitment, led by the MacArthur Foundation and the Sloan Foundation, who provided US$20 million and US$5 million, respectively. The additional US$25 million came from five cornerstone institutions—the Field Museum, Harvard University, the Marine Biological Laboratory, the Missouri Botanical Garden, and the Smithsonian Institutio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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