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Brad M. Rader English 1100 Section 124 Dr. Gene Miller March 10, 2000 `` The Fish '' Poems to me are an look of a individual '' s mentality on a peculiar scene or topic. By reading a verse form a individual can be enlightened and take an apprehension of what they are really reading. In `` The Fish '' , I personally was caught up in all the exhilaration because I know what it feels like to catch a truly mammoth fish. This verse form, to me, shows an mentality on nature that I have ever been accustomed to. In composing verse form there is a whole class of tools and techniques you can utilize to do the verse form great alternatively of mediocre. In this verse form, to me imagery plays a really large function. When you read the verse form the imagination lets you non merely believe about what you are reading but besides it lets you really see it in your caput. Another tool used in the verse form is personification. It can assist the writer do so much more explicating than the usual. Personification in this verse form is merely every bit of import as the usage of imagination is. Besides, the ideas/themes of this verse form are really important every bit good to do it a really good verse form. When Elizabeth Bishop put all of these tools together she made `` The Fish '' what it is today, a great verse form. The usage of imagination in this verse form had to be used in merely the right manner. If it was non used decently so the verse form could hold lost all significance and apprehension, doing the verse form reasonably much useless. When Bishop uses lines like this the imagination is shown really good. `` Here and at that place his brown tegument hung in strips like ancient wallpaper. '' That line merely makes you see the fish '' s brown tegument and how it is hanging like ancient wallpaper. Another line Bishop uses is when she is speaking about the fish '' s tegument and depict it as forms like full-brown roses. The imagination in a verse form merely gives it so much more pregnant and such a better advantage over verse forms that do non hold any imagination in them. Everybody has read something and it did non do any sense at all. Imagery allows the reader to read the verse form and non acquire confused about what the writer is seeking to acquire across to the reader. So, the importance of imagination is of import non merely in poesy but besides in other types of authorship every bit good. Another tool that Bishop uses in `` The Fish '' is personification. Personification is giving human features to something that is non human. It lets us understand what is being written better because we can associate it to ourselves and things we do and see in our ain lives. A twosome illustrations are: a five-haired face fungus of wisdom draging from his hurting jaw�”like decorations with their threads frayed and hesitating. In the first illustration, the personification is the usage of the word `` face fungus. '' To us merely work forces have face funguss on their faces. But it helps the reader acquire a image in their caput of what is seeking to be described. Besides, in the 2nd illustration the personification is where Bishop talks about the threads. To us merely people get threads for things they do. We do non believe of fish holding and have oning threads. But it lets us see and understand in a better and more effectual manner. Which is what the writer wants from us anyhow. Last of all the ideas/themes of the verse form are of import and should non be left out. The thoughts and subjects that go through my caput when I read the verse forms are things like `` I want to travel out and catch a truly enormous fish '' and `` do non undervalue anything until you have gave it a good analysis. The thoughts and subjects are non truly as of import to me in this verse form. But on the other manus they could be the most of import tools in another verse form. It truly has to make with what the verse form is about and what the writer is taking to make or carry through with the verse form. I truly enjoyed reading `` The Fish. '' It is truly a verse form that will lodge out in my head for a long clip. I think that the tools that Bishop used makes the verse form more sympathetic and suited for me to bask. Imagery, personification, and ideas/themes truly do this verse form stick out above the remainder in the class. If you want to read a truly good verse form that makes good sense so read `` The Fish! ''

A Few Examples

Dragonfishes and hatchetfishes ( Stomiiformes ) are characterized by luxuriant agreements of photophores. They may feature glowing feelers, photophores under their eyes, and others along their ventral ( underneath ) sides. A few stomiatoid fishes such as Malacosteus Niger have photophores that produce two radically different frequences of visible radiation: one behind the oculus that produces bluish visible radiation and one under the oculus that can bring forth ruddy visible radiation. This is unusual because long moving ridge red light dissipates more rapidly as it passes deeper into the ocean, where short beckon bluish green visible radiation is the norm. Using specialised pigments capable of comprehending ruddy visible radiation, fishes like Malacosteus Niger can pass on with one another via a private wavelength and besides visualise quarry.


The term fish is applied to a assortment of craniates of several evolutionary lines. It describes a life-form instead than a systematic group. As members of the phylum Chordata, fish portion certain characteristics with other craniates. These characteristics are gill slits at some point in the life rhythm, a notochord, or skeletal supporting rod, a dorsal hollow nervus cord, and a tail. Populating fishes represent some five categories, which are as distinguishable from one another as are the four categories of familiar air-breathing animals—amphibians, reptilians, birds, and mammals. For illustration, the jawless fishes ( Agnatha ) have gills in pouches and deficiency limb girdles. Extant jawless vertebrates are the lamper eels and the slime eelss. As the name implies, the skeletons of fishes of the category Chondrichthyes ( from chondr, “cartilage, ” and ichthyes, “fish” ) are made wholly of gristle. Modern fish of this category deficiency a swim vesica, and their graduated tables and dentitions are made up of the same platelike stuff. Sharks, skates, and beams are illustrations of cartilaginous fishes. The bony fishes are by far the largest category. Examples range from the bantam sea Equus caballus to the 450-kg ( 1,000-pound ) blue marlin, from the planate colloidal suspensions and flounders to the boxlike blowfishs and ocean sunfishes. Unlike the graduated tables of the cartilaginous fishes, those of bony fishes, when nowadays, turn throughout life and are made up of thin, overlapping home bases of bone. Bony fishes besides have an operculum that covers the gill slits.

The survey of fishes, the scientific discipline of ichthyology, is of wide importance. Fishs are of involvement to worlds for many grounds, the most of import being their relationship with and dependance on the environment. A more obvious ground for involvement in fishes is their function as a moderate but of import portion of the world’s nutrient supply. This resource, one time thought limitless, is now realized to be finite and in delicate balance with the biological, chemical, and physical factors of the aquatic environment. Overfishing, pollution, and change of the environment are the main enemies of proper piscaries direction, both in fresh Waterss and in the ocean. ( For a elaborate treatment of the engineering and economic sciences of piscaries, see commercial fishing. ) Another practical ground for analyzing fishes is their usage in disease control. As marauders on mosquito larvae, they help control malaria and other mosquito-borne diseases.

There are aesthetic and recreational grounds for an involvement in fishes. Millions of people keep unrecorded fishes in place fish tanks for the simple pleasance of detecting the beauty and behavior of animate beings otherwise unfamiliar to them. Aquarium fishes provide a personal challenge to many aquarists, leting them to prove their ability to maintain a little subdivision of the natural environment in their places. Sportfishing is another manner of basking the natural environment, besides indulged in by 1000000s of people every twelvemonth. Interest in fish tank fishes and sportfishing supports multimillion-dollar industries throughout the universe.

Structural diverseness

Fishs have been in being for more than 450 million old ages, during which clip they have evolved repeatedly to suit into about every imaginable type of aquatic home ground. In a sense, land craniates are merely extremely modified fishes: when fishes colonized the land home ground, they became tetrapod ( four-legged ) land craniates. The popular construct of a fish as a slippery, streamlined aquatic animate being that possesses fives and breathes by gills applies to many fishes, but far more fishes deviate from that construct than conform to it. For illustration, the organic structure is linear in many signifiers and greatly shortened in others ; the organic structure is flattened in some ( chiefly in bottom-dwelling fishes ) and laterally compressed in many others ; the fives may be intricately extended, organizing intricate forms, or they may be reduced or even lost ; and the places of the oral cavity, eyes, anterior nariss, and gill gaps vary widely. Air breathers have appeared in several evolutionary lines.

Distribution and copiousness

About all natural organic structures of H2O bear fish life, the exclusions being really hot thermic pools and highly salt-alkaline lakes, such as the Dead Sea in Asia and the Great Salt Lake in North America. The present distribution of fishes is a consequence of the geological history and development of the Earth every bit good as the ability of fishes to undergo evolutionary alteration and to accommodate to the available home grounds. Fishs may be seen to be distributed harmonizing to home ground and harmonizing to geographical country. Major home ground differences are marine and fresh water. For the most portion, the fishes in a marine home ground differ from those in a fresh water home ground, even in next countries, but some, such as the salmon, migrate from one to the other. The fresh water home grounds may be seen to be of many sorts. Fishs found in mountain downpours, Arctic lakes, tropical lakes, temperate watercourses, and tropical rivers will all differ from each other, both in obvious gross construction and in physiological properties. Even in closely next home grounds where, for illustration, a tropical mountain downpour enters a lowland watercourse, the fish zoology will differ. The marine home grounds can be divided into deep ocean floors ( benthal ) , mid-water Oceanic ( bathypelagic ) , surface Oceanic ( pelagic ) , bouldery seashore, flaxen seashore, muddy shores, bays, estuaries, and others. Besides, for illustration, bouldery coastal shores in tropical and temperate parts will hold different fish zoology, even when such home grounds occur along the same coastline.

Although much is known about the present geographical distribution of fishes, far less is known about how that distribution came about. Many parts of the fish zoology of the fresh Waterss of North America and Eurasia are related and doubtless have a common beginning. The zoology of Africa and South America are related, highly old, and likely an look of the floating apart of the two continents. The zoology of southern Asia is related to that of Central Asia, and some of it appears to hold entered Africa. The highly big shore-fish zoology of the Indian and tropical Pacific oceans comprise a related composite, but the tropical shore zoology of the Atlantic, although incorporating Indo-Pacific constituents, is comparatively limited and likely younger. The Arctic and Antarctic marine zoologies are rather different from each other. The shore zoology of the North Pacific is rather distinguishable, and that of the North Atlantic more limited and likely younger. Pelagic pelagic fishes, particularly those in deep Waterss, are similar the universe over, demoing small geographical isolation in footings of household groups. The deep pelagic home ground is really much the same throughout the universe, but species differences do be, demoing geographical countries determined by pelagic currents and H2O multitudes.

Life history

Correlated with their version to an highly broad assortment of home grounds is the highly broad assortment of life rhythms that fishes show. The great bulk hatch from comparatively little eggs a few yearss to several hebdomads or more after the eggs are scattered in the H2O. Newly hatched immature are still partly undeveloped and are called larvae until organic structure constructions such as fives, skeleton, and some variety meats are to the full formed. Larval life is frequently really short, normally less than a few hebdomads, but it can be really long, some lamper eels go oning as larvae for at least five old ages. Young and larval fishes, before making sexual adulthood, must turn well, and their little size and other factors frequently dictate that they live in a home ground different than that of the grownups. For illustration, most tropical Marine shore fishes have pelagic larvae. Larval nutrient besides is different, and larval fishes frequently live in shallow Waterss, where they may be less exposed to marauders.


A fish is any member of a group of animate beings that consist of all gill-bearing aquatic vertebrate animate beings that lack limbs with figures. They form a sister group to the urochordates, together organizing the olfactores. Included in this definition are the life slime eels, lamper eels, and cartilaginous and cadaverous fish every bit good as assorted nonextant related groups. Tetrapods emerged within lobe-finned fishes, so cladistically they are fish as good. However, traditionally fish are rendered disused or paraphyletic by excepting the tetrapods ( i.e. , the amphibious vehicles, reptilians, birds and mammals which all descended from within the same lineage ) . Because in this mode the term `` fish '' is defined negatively as a paraphyletic group, it is non considered a formal taxonomic grouping in systematic biological science. The traditional term Piscess ( besides ichthyes ) is considered a typological, but non a phyletic categorization.

The earliest beings that can be classified as fish were soft-bodied chordates that first appeared during the Welsh period. Although they lacked a true spinal column, they possessed notochords which allowed them to be more nimble than their invertebrate opposite numbers. Fish would go on to germinate through the Paleozoic epoch, diversifying into a broad assortment of signifiers. Many fish of the Paleozoic developed external armour that protected them from marauders. The first fish with jaws appeared in the Silurian period, after which many ( such as sharks ) became formidable Marine marauders instead than merely the quarry of arthropods.


The term `` fish '' most exactly describes any non-tetrapod vertebrate ( i.e. an animate being with a skull and in most instances a anchor ) that has gills throughout life and whose limbs, if any, are in the form of fives. Unlike groupings such as birds or mammals, fish are non a individual clade but a paraphyletic aggregation of taxa, including slime eelss, lamper eels, sharks and beams, ray-finned fish, Latimeria chalumnaes, and lungfish. Indeed, lungfish and Latimeria chalumnaes are closer relations of tetrapods ( such as mammals, birds, amphibious vehicles, etc. ) than of other fish such as ray-finned fish or sharks, so the last common ascendant of all fish is besides an ascendant to tetrapods. As paraphyletic groups are no longer recognised in modern systematic biological science, the usage of the term `` fish '' as a biological group must be avoided.

Many types of aquatic animate beings normally referred to as `` fish '' are non fish in the sense given above ; illustrations include shellfish, cuttlefish, starfish, crayfish and jellyfish. In earlier times, even life scientists did non do a differentiation – 16th century natural historiographers classified besides seals, giants, amphibious vehicles, crocodiles, even hippopotamuses, every bit good as a host of aquatic invertebrates, as fish. However, harmonizing to the definition above, all mammals, including blowers like giants and mahimahis, are non fish. In some contexts, particularly in aquaculture, the true fish are referred to as finfish ( or fin fish ) to separate them from these other animate beings.

Each standard has exclusions. Tuna, swordfish, and some species of sharks show some warm-blooded adaptations—they can heat their organic structures significantly above ambient H2O temperature. Streamlining and swimming public presentation varies from fish such as tuna, salmon, and knuckleboness that can cover 10–20 body-lengths per second to species such as eels and beams that swim no more than 0.5 body-lengths per second. Many groups of freshwater fish infusion O from the air every bit good as from the H2O utilizing a assortment of different constructions. Lungfish have paired lungs similar to those of tetrapods, gouramis have a construction called the maze organ that performs a similar map, while many catfish, such as Corydoras extract O via the bowel or tummy. Body form and the agreement of the fives is extremely variable, covering such apparently un-fishlike signifiers as walruss, pufferfish, anglerfish, and guzzlers. Similarly, the surface of the tegument may be naked ( as in moray eels ) , or covered with graduated tables of a assortment of different types normally defined as placoid ( typical of sharks and beams ) , cosmoid ( fossil lungfish and Latimeria chalumnaes ) , ganoid ( assorted dodo fish but besides living gars and bichirs ) , cycloid, and ctenoid ( these last two are found on most cadaverous fish ) . There are even fish that live largely on land or put their eggs on land near H2O. Mudskippers feed and interact with one another on mudflats and travel submerged to conceal in their tunnels. A individual, an undescribed species of Phreatobius, has been called a true `` land fish '' as this worm-like mudcat purely lives among boggy foliage litter. Many species live in belowground lakes, belowground rivers or aquifers and are popularly known as cavefish.

Fish species diverseness is approximately divided every bit between Marine ( pelagic ) and freshwater ecosystems. Coral reefs in the Indo-Pacific constitute the centre of diverseness for Marine fishes, whereas Continental fresh water fishes are most diverse in big river basins of tropical rain forests, particularly the Amazon, Congo, and Mekong basins. More than 5,600 fish species inhabit Neotropical fresh waters entirely, such that Neotropical fishes represent about 10 % of all vertebrate species on the Earth. Exceptionally rich sites in the Amazon basin, such as Cantão State Park, can incorporate more freshwater fish species than occur in all of Europe.


Most fish exchange gases utilizing gills on either side of the throat. Gills consist of threadlike constructions called fibrils. Each fibril contains a capillary web that provides a big surface country for interchanging O and C dioxide. Fish exchange gases by drawing oxygen-rich H2O through their oral cavities and pumping it over their gills. In some fish, capillary blood flows in the opposite way to the H2O, doing countercurrent exchange. The gills push the oxygen-poor H2O out through gaps in the sides of the throat. Some fish, like sharks and lamper eels, possess multiple gill gaps. However, cadaverous fish have a individual gill opening on each side. This gap is hidden beneath a protective bony screen called an operculum.

Fish from multiple groups can populate out of the H2O for extended periods. Amphibious fish such as the mudspringer can populate and travel about on land for up to several yearss, or live in stagnant or otherwise O depleted H2O. Many such fish can take a breath air via a assortment of mechanisms. The tegument of anguillid eels may absorb O straight. The buccal pit of the electric eel may take a breath air. Catfish of the households Loricariidae, Callichthyidae, and Scoloplacidae absorb air through their digestive piece of lands. Lungfish, with the exclusion of the Australian lungfish, and bichirs have paired lungs similar to those of tetrapods and must come up to quaff fresh air through the oral cavity and base on balls spent air out through the gills. Gar and grindle have a vascularized swim vesica that maps in the same manner. Loaches, trahiras, and many catfish breathe by go throughing air through the intestine. Mudskippers breathe by absorbing O across the tegument ( similar to toads ) . A figure of fish have evolved alleged accoutrement external respiration variety meats that extract O from the air. Labyrinth fish ( such as gouramis and bettas ) have a labyrinth organ above the gills that performs this map. A few other fish have constructions resembling labyrinth variety meats in signifier and map, most notably shellflowers, pikeheads, and the Clariidae catfish household.


Fishs have a closed-loop circulatory system. The bosom pumps the blood in a individual cringle throughout the organic structure. In most fish, the bosom consists of four parts, including two Chamberss and an entryway and issue. The first portion is the fistula venosus, a thin-walled pouch that collects blood from the fish 's venas before leting it to flux to the 2nd portion, the atrium, which is a big muscular chamber. The atrium serves as a one-way anteroom, sends blood to the 3rd portion, ventricle. The ventricle is another thick-walled, muscular chamber and it pumps the blood, foremost to the 4th portion, bulbus arteriosus, a big tubing, and so out of the bosom. The bulbus arteriosus connects to the aorta, through which blood flows to the gills for oxygenation.

Sensory and nervous system

Most fish possess extremely developed sense variety meats. About all daylight fish have color vision that is at least every bit good as a homo 's ( see vision in fishes ) . Many fish besides have chemoreceptors that are responsible for extraordinary senses of gustatory sensation and odor. Although they have ears, many fish may non hear really good. Most fish have sensitive receptors that form the sidelong line system, which detects soft currents and quivers, and senses the gesture of nearby fish and quarry. Some fish, such as catfish and sharks, have variety meats that detect weak electric currents on the order of mV. Other fish, like the South American electric fishes Gymnotiformes, can bring forth weak electric currents, which they use in pilotage and societal communicating.

Vision is an of import sensory system for most species of fish. Fish eyes are similar to those of tellurian craniates like birds and mammals, but have a more spherical lens. Their retinas by and large have both rods and cones ( for scotopic and photopic vision ) , and most species have colour vision. Some fish can see ultraviolet and some can see polarized visible radiation. Amongst jawless fish, the lamper eel has well-developed eyes, while the slime eels has merely crude ocelluss. Fish vision shows version to their ocular environment, for illustration deep sea fishes have eyes suited to the dark environment.

Professor James D. Rose of the University of Wyoming claimed the survey was flawed since it did non supply cogent evidence that fish possess `` witting consciousness, peculiarly a sort of consciousness that is meaningfully similar ours '' . Rose argues that since fish encephalons are so different from human encephalons, fish are likely non witting in the mode worlds are, so that reactions similar to human reactions to trouble alternatively hold other causes. Rose had published a survey a twelvemonth earlier reasoning that fish can non experience pain because their encephalons lack a neopallium. However, carnal behaviourist Temple Grandin argues that fish could still hold consciousness without a neopallium because `` different species can utilize different encephalon constructions and systems to manage the same maps. ''

Muscular system

Most fish move by alternately undertaking paired sets of musculuss on either side of the anchor. These contractions form S-shaped curves that move down the organic structure. As each curve reaches the back five, rearward force is applied to the H2O, and in concurrence with the fives, moves the fish forward. The fish 's fives function like an aeroplane 's flaps. Fives besides increase the tail 's surface country, increasing velocity. The streamlined organic structure of the fish decreases the sum of clash from the H2O. Since organic structure tissue is denser than H2O, fish must counterbalance for the difference or they will drop. Many bony fish have an internal organ called a swim vesica that adjusts their perkiness through use of gases.


Certain species of fish maintain elevated organic structure temperatures. Endothermic teleosts ( cadaverous fish ) are all in the suborder Scombroidei and include the gars, tunas, and one species of `` crude '' mackerel ( Gasterochisma melampus ) . All sharks in the household Lamnidae – shortfin mako, long fin mako, white, Lamna nasus, and salmon shark – are endothermal, and grounds suggests the trait exists in household Alopiidae ( thresher sharks ) . The grade of endothermy varies from the gar, which warm merely their eyes and encephalon, to bluefin tuna and Lamna nasus sharks who maintain organic structure temperatures elevated in surplus of 20 °C above ambient H2O temperatures. See besides gigantothermy. Endothermy, though metabolically dearly-won, is thought to supply advantages such as increased musculus strength, higher rates of cardinal nervous system processing, and higher rates of digestion.

Generative system

Fish ovaries may be of three types: gymnovarian, secondary gymnovarian or cystovarian. In the first type, the oocytes are released straight into the coelomic pit and so come in the ostium, so through the Fallopian tube and are eliminated. Secondary gymnovarian ovaries shed ova into the celom from which they go straight into the Fallopian tube. In the 3rd type, the oocytes are conveyed to the outside through the Fallopian tube. Gymnovaries are the crude status found in lungfish, sturgeon, and grindle. Cystovaries characterize most teleosts, where the ovary lms has continuity with the Fallopian tube. Secondary gymnovaries are found in salmonids and a few other teleosts.

Over 97 % of all known fish are oviparous, that is, the eggs develop outside the female parent 's organic structure. Examples of oviparous fish include salmon, goldfish, cichlids, tuna, and eels. In the bulk of these species, fertilization takes topographic point outside the female parent 's organic structure, with the male and female fish casting their gametes into the encompassing H2O. However, a few oviparous fish pattern internal fertilisation, with the male utilizing some kind of intromittent organ to present sperm into the venereal gap of the female, most notably the oviparous sharks, such as the horn shark, and oviparous beams, such as skates. In these instances, the male is equipped with a brace of modified pelvic fives known as claspers.

The freshly hatched immature of oviparous fish are called larvae. They are normally ill formed, carry a big yolk pouch ( for nutriment ) , and are really different in visual aspect from juvenile and grownup specimens. The larval period in oviparous fish is comparatively short ( normally merely several hebdomads ) , and larvae quickly grow and alteration visual aspect and construction ( a procedure termed metabolism ) to go juveniles. During this passage larvae must exchange from their yolk pouch to feeding on zooplankton quarry, a procedure which depends on typically unequal zooplankton denseness, hungering many larvae.

Some species of fish are live-bearing. In such species the female parent retains the eggs and nourishes the embryos. Typically, live-bearing fish have a construction correspondent to the placenta seen in mammals linking the female parent 's blood supply with that of the embryo. Examples of live-bearing fish include the surf-perches, splitfins, and lemon shark. Some live-bearing fish exhibit oophagy, in which the developing embryos eat other eggs produced by the female parent. This has been observed chiefly among sharks, such as the shortfin mako and Lamna nasus, but is known for a few bony fish every bit good, such as the halfbeak Nomorhamphus ebrardtii. Intrauterine cannibalism is an even more unusual manner of vivipary, in which the largest embryos eat weaker and smaller siblings. This behaviour is besides most normally found among sharks, such as the Grey nurse shark, but has besides been reported for Nomorhamphus ebrardtii.


Like other animate beings, fish suffer from diseases and parasites. To forestall disease they have a assortment of defences. Non-specific defences include the tegument and graduated tables, every bit good as the mucous secretion bed secreted by the cuticle that traps and inhibits the growing of micro-organisms. If pathogens breach these defences, fish can develop an inflammatory response that increases blood flow to the septic part and delivers white blood cells that attempt to destruct pathogens. Specific defenses respond to peculiar pathogens recognised by the fish 's organic structure, i.e. , an immune response. In recent old ages, vaccinums have become widely used in aquaculture and besides with cosmetic fish, for illustration furunculosis vaccinums in farmed salmon and koi herpes virus in koi.

Immune system

Immune variety meats vary by type of fish. In the jawless fish ( lamper eels and slime eels ) , true lymphoid variety meats are absent. These fish rely on parts of lymphoid tissue within other variety meats to bring forth immune cells. For illustration, erythrocytes, macrophages and plasma cells are produced in the anterior kidney ( or pronephros ) and some countries of the intestine ( where granulocytes mature. ) They resemble crude bone marrow in hagfish. Cartilaginous fish ( sharks and beams ) have a more advanced immune system. They have three specialized variety meats that are alone to Chondrichthyes ; the epigonal variety meats ( lymphoid tissue similar to mammalian bone ) that surround the sex glands, the Leydig 's organ within the walls of their gorge, and a coiling valve in their bowel. These variety meats house typical immune cells ( granulocytes, lymph cells and plasma cells ) . They besides possess an identifiable Thymus and a well-developed lien ( their most of import immune organ ) where assorted lymph cells, plasma cells and macrophages develop and are stored. Chondrostean fish ( sturgeons, paddlefish, and bichirs ) possess a major site for the production of granulocytes within a mass that is associated with the meninxs ( membranes environing the cardinal nervous system. ) Their bosom is often covered with tissue that contains lymph cells, reticulate cells and a little figure of macrophages. The chondrostean kidney is an of import hematopoietic organ ; where red blood cells, granulocytes, lymph cells and macrophages develop.

Like chondrostean fish, the major immune tissues of bony fish ( or teleostei ) include the kidney ( particularly the anterior kidney ) , which houses many different immune cells. In add-on, teleost fish possess a Thymus, lien and scattered immune countries within mucosal tissues ( e.g. in the tegument, gills, intestine and sex glands ) . Much like the mammalian immune system, teleost red blood cells, neutrophils and granulocytes are believed to shack in the spleen whereas lymph cells are the major cell type found in the Thymus. In 2006, a lymphatic system similar to that in mammals was described in one species of teleost fish, the zebrafish. Although non confirmed as yet, this system presumptively will be where naif ( unstimulated ) T cells accumulate while waiting to meet an antigen.


Fish characteristic conspicuously in art and literature, in films such as Finding Nemo and books such as The Old Man and the Sea. Large fish, peculiarly sharks, have often been the topic of horror films and thrillers, most notably the novel Jaws, which spawned a series of movies of the same name that in bend divine similar movies or lampoons such as Shark Tale and Snakehead Terror. Piranhas are shown in a similar visible radiation to sharks in movies such as Piranha ; nevertheless, contrary to popular belief, the red-bellied marauder is really a by and large timid scavenger species that is improbable to harm worlds. In the Book of Jonah a `` great fish '' swallowed Jonah the Prophet. Legends of half-human, half-fish mermaids have featured in folklore, including the narratives of Hans Christian Andersen.

Fish subjects have symbolic significance in many faiths. The fish is used frequently as a symbol by Christians to stand for Jesus, or Christianity in general ; the Gospels besides refer to `` fishers of work forces '' and feeding the battalion. In the dhamma of Buddhism the fish symbolize felicity as they have complete freedom of motion in the H2O. Often drawn in the signifier of carp which are regarded in the Orient as sacred on history of their elegant beauty, size and life-span. Among the divinities said to take the signifier of a fish are Ika-Roa of the Polynesians, Dagon of assorted ancient Semitic peoples, the shark-gods of Hawaiʻi and Matsya of the Hindus.

Shoal or school

A random gathering of fish simply utilizing some localised resource such as nutrient or nesting sites is known merely as an collection. When fish come together in an synergistic, societal grouping, so they may be organizing either a shoal or a school depending on the grade of administration. A shoal is a slackly organised group where each fish swims and eatages independently but is attracted to other members of the group and adjusts its behavior, such as swimming velocity, so that it remains close to the other members of the group. Schools of fish are much more tightly organised, synchronizing their swimming so that all fish move at the same velocity and in the same way. Shallowing and schooling behavior is believed to supply a assortment of advantages.

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