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Homocercal
Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as seen in sharks. Apart from the tail or caudal fin, fish fins have no direct connection with the spine and are supported only by muscles. Their principal function is to help the fish swim. Fins located in different places on the fish serve different purposes such as moving forward, turning, keeping an upright position or stopping. Most fish use fins when swimming, flying fish use pectoral fins for gliding, and frogfish use them for crawling. Fins can also be used for other purposes; male sharks and mosquitofish use a modified fin to deliver sperm, thresher sharks use their caudal fin to stun prey, reef stonefish have spines in their dorsal fins that inject venom, anglerfish use the first spine of their dorsal fin like a fishing rod to lure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caudal Fin
Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as seen in sharks. Apart from the tail or caudal fin, fish fins have no direct connection with the spine and are supported only by muscles. Their principal function is to help the fish swim. Fins located in different places on the fish serve different purposes such as moving forward, turning, keeping an upright position or stopping. Most fish use fins when swimming, flying fish use pectoral fins for gliding, and frogfish use them for crawling. Fins can also be used for other purposes; male sharks and mosquitofish use a modified fin to deliver sperm, thresher sharks use their caudal fin to stun prey, reef stonefish have spines in their dorsal fins that inject venom, anglerfish use the first spine of their dorsal fin like a fishing rod to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths. The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark (''Etmopterus perryi''), a deep sea species that is only in length, to the whale shark (''Rhincodon typus''), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths up to . They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kopie Van DSC00282
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Kopie is a village in the administrative district of Gmina Godziesze Wielkie, within Kalisz County, Greater Poland Voivodeship, in west-central Poland. References Kopie Kopie is a village in the administrative district of Gmina Godziesze Wielkie, within Kalisz County __NOTOC__ Kalisz County ( pl, powiat kaliski) is a unit of territorial administration and local government (powiat) in Greater Poland Voivodeship, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of Taxonomy (biology), 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 reproduction, produce Fertility, fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), 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 binomial nomenclature, 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 specifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bobasatrania
''Bobasatrania'' is an extinct genus of prehistoric bony fish that survived the Permian-Triassic extinction event. Fossils of ''Bobasatrania'' were found in beds of Changhsingian (late Permian) to Ladinian (Middle Triassic) age. It was most speciose during the Early Triassic. The genus was named after the locality Bobasatrana in northeast Madagascar, from where the type species was described. The genus originated during the late Permian, survived the Permian-Triassic extinction event, and underwent a speciation event during the Triassic (approx 240M years BP) in the shallow coastal waters off the Pangaean supercontinent. Their fossils are therefore found throughout the world, with some of the best examples coming from the Wapiti Lake region of British Columbia, Canada. Past Lives: Chronicles of Canadian Paleontology They have a distinctive diamond-shaped body, forked tail and long thin pectoral fins. The larger species are up to in length, though there are also smaller sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean Sunfish
The ocean sunfish or common mola (''Mola mola'') is one of the largest bony fish in the world. It was misidentified as the heaviest bony fish, which was actually a different species, '' Mola alexandrini''. Adults typically weigh between . The species is native to tropical and temperate waters around the world. It resembles a fish head without a tail, and its main body is flattened laterally. Sunfish can be as tall as they are long when their dorsal and ventral fins are extended. Sunfish are generalist predators that consume largely small fish, fish larvae, squid, and crustaceans. Sea jellies and salps, once thought to be the primary prey of sunfish, make up only 15% of a sunfish's diet. Females of the species can produce more eggs than any other known vertebrate, up to 300,000,000 at a time. Sunfish fry resemble miniature pufferfish, with large pectoral fins, a tail fin, and body spines uncharacteristic of adult sunfish. Adult sunfish are vulnerable to few natural predato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clades
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species ( extinct or extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acanthodii
Acanthodii or acanthodians is an extinct class of gnathostomes (jawed fishes), typically considered a paraphyletic group. They are currently considered to represent a grade of various fish lineages leading up to the extant Chondrichthyes, which includes living sharks, rays, and chimaeras. Acanthodians possess a mosaic of features shared with both osteichthyans (bony fish) and chondrichthyans (cartilaginous fish). In general body shape, they were similar to modern sharks, but their epidermis was covered with tiny rhomboid platelets like the scales of holosteians ( gars, bowfins). A lower Silurian species, '' Fanjingshania renovata'', attributed to Climatiiformes is the oldest chondrichthyan with known anatomical features. The popular name "spiny sharks" is because they were superficially shark-shaped, with a streamlined body, paired fins, a strongly upturned tail, and stout, largely immovable bony spines supporting all the fins except the tail—hence, "spiny sharks". However ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lampanyctodes Hectoris (fins)
Hector's lanternfish (''Lampanyctodes hectoris'') is a lanternfish in the family Myctophidae, the only species in the genus ''Lampanyctodes''. It is named after James Hector. It is a widespread marine fish, known from shallow tropical waters in the south-eastern Atlantic, from the western Pacific off Australia and New Zealand, and from the eastern Pacific off Chile. It is one of the few species of lanternfishes to inhabit shallow waters, and in those waters it is one of the most abundant species of fish, and central to the food chain of the upper continental slope. The abundance is due to its high fecundity — it spawns multiple times in the winter so that the fry can take advantage of the spring bloom of krill. It grows up to standard length (SL) and may reach the age of 3 years. It reaches sexual maturity at approximately 50 mm SL and age of one year. Hector's lanternfish is fished commercially using seine nets in the waters off South Africa, where catches ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homology (biology)
In biology, homology is similarity due to shared ancestry between a pair of structures or genes in different taxa. A common example of homologous structures is the forelimbs of vertebrates, where the wings of bats and birds, the arms of primates, the front flippers of whales and the forelegs of four-legged vertebrates like dogs and crocodiles are all derived from the same ancestral tetrapod structure. Evolutionary biology explains homologous structures adapted to different purposes as the result of descent with modification from a common ancestor. The term was first applied to biology in a non-evolutionary context by the anatomist Richard Owen in 1843. Homology was later explained by Charles Darwin's theory of evolution in 1859, but had been observed before this, from Aristotle onwards, and it was explicitly analysed by Pierre Belon in 1555. In developmental biology, organs that developed in the embryo in the same manner and from similar origins, such as from matc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triggerfish
Triggerfish are about 40 species of often brightly colored fish of the family Balistidae. Often marked by lines and spots, they inhabit tropical and subtropical oceans throughout the world, with the greatest species richness in the Indo-Pacific. Most are found in relatively shallow, coastal habitats, especially at coral reefs, but a few, such as the oceanic triggerfish (''Canthidermis maculata''), are pelagic. While several species from this family are popular in the marine aquarium trade, they are often notoriously ill-tempered. Anatomy and appearance The largest member of the family, the stone triggerfish (''Pseudobalistes naufragium'') reaches , but most species have a maximum length between . Triggerfish have an oval-shaped, highly compressed body. The head is large, terminating in a small but strong-jawed mouth with teeth adapted for crushing shells. The eyes are small, set far back from the mouth, at the top of the head. The anterior dorsal fin is reduced to a set of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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