fbpx
Wikipedia

Fish

January 31, 2023

For fish as eaten by humans, see Fish as food. For the superclass containing the vast majority of living fish, see Osteichthyes. For other uses, see Fish (disambiguation).

Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts.

Fish
Temporal range: 535–0 Ma Middle Cambrian - Recent
Giant grouper swimming among schools of other fish
Head-on view of a red lionfish
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Olfactores
Subphylum: Vertebrata
Groups included
Jawless fish
†Armoured fish
†Spiny sharks
Cartilaginous fish
Bony fish
Ray-finned fish
Lobe-finned fish
Cladistically included but traditionally excluded taxa
Tetrapods

The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods.

Most fish are ectothermic ("cold-blooded"), allowing their body temperatures to vary as ambient temperatures change, though some of the large active swimmers like white shark and tuna can hold a higher core temperature.[1][2] Fish can acoustically communicate with each other, most often in the context of feeding, aggression or courtship.[3]

Fish are abundant in most bodies of water. They can be found in nearly all aquatic environments, from high mountain streams (e.g., char and gudgeon) to the abyssal and even hadal depths of the deepest oceans (e.g., cusk-eels and snailfish), although no species has yet been documented in the deepest 25% of the ocean.[4] With 34,300 described species, fish exhibit greater species diversity than any other group of vertebrates.[5]

Fish are an important resource for humans worldwide, especially as food. Commercial and subsistence fishers hunt fish in wild fisheries or farm them in ponds or in cages in the ocean (in aquaculture). They are also caught by recreational fishers, kept as pets, raised by fishkeepers, and exhibited in public aquaria. Fish have had a role in culture through the ages, serving as deities, religious symbols, and as the subjects of art, books and movies.

Tetrapods (amphibians, reptiles, birds and mammals) emerged within lobe-finned fishes, so cladistically they are fish as well. However, traditionally fish (pisces or ichthyes) are rendered paraphyletic by excluding the tetrapods, and are therefore not considered a formal taxonomic grouping in systematic biology, unless it is used in the cladistic sense, including tetrapods,[6][7] although usually "vertebrate" is preferred and used for this purpose (fish plus tetrapods) instead. Furthermore, cetaceans, although mammals, have often been considered fish by various cultures and time periods.

Etymology

The word for fish in English and the other Germanic languages (German Fisch; Gothic fisks) is inherited from Proto-Germanic, and is related to the Latin piscis and Old Irish īasc, though the exact root is unknown; some authorities reconstruct a Proto-Indo-European root *peysk-, attested only in Italic, Celtic, and Germanic.[8][9][10][11]

The English word once had a much broader usage than its current biological meaning. Names such as starfish, jellyfish, shellfish and cuttlefish attest to almost any fully aquatic animal (including whales) once being fish. "Correcting" such names (e.g. to sea star) is an attempt to retroactively apply the current meaning of fish to words that were coined when it had a different meaning.[citation needed]

Evolution

Main article: Evolution of fish

Fish, as vertebrata, developed as sister of the tunicata. As the tetrapods emerged deep within the fishes group, as sister of the lungfish, characteristics of fish are typically shared by tetrapods, including having vertebrae and a cranium.

 
Dunkleosteus was a gigantic, 10-metre (33 ft) long prehistoric fish of class Placodermi.
 
Lower jaw of the placoderm Eastmanosteus pustulosus, showing the shearing structures ("teeth") on its oral surface; from the Devonian of Wisconsin

Early fish from the fossil record are represented by a group of small, jawless, armored fish known as ostracoderms. Jawless fish lineages are mostly extinct. An extant clade, the lampreys may approximate ancient pre-jawed fish. The first jaws are found in Placodermi fossils. They lacked distinct teeth, having instead the oral surfaces of their jaw plates modified to serve the various purposes of teeth. The diversity of jawed vertebrates may indicate the evolutionary advantage of a jawed mouth. It is unclear if the advantage of a hinged jaw is greater biting force, improved respiration, or a combination of factors.

Fish may have evolved from a creature similar to a coral-like sea squirt, whose larvae resemble primitive fish in important ways. The first ancestors of fish may have kept the larval form into adulthood (as some sea squirts do today).

Phylogeny

Fishes are a paraphyletic group: that is, any clade containing all fish also contains the tetrapods, which are not fish (though they include fish-shaped forms, such as Whales and Dolphins or the extinct ichthyosaurs, which acquired a fish-like body shape due to secondary aquatic adaptation, see evolution of cetaceans).

The following cladogram shows clades - some with, some without extant relatives - that are traditionally considered as "fishes" (cyan line) and the tetrapods (four-limbed vertebrates), which are mostly terrestrial. Extinct groups are marked with a dagger (†).

Vertebrata/

†Euconodonta 

†Pteraspidomorphi 

†Thelodonti 

†Anaspida 

†Galeaspida  

†Pituriaspida 

†Osteostraci 

Gnathostomata

"†Placodermi" (armoured fishes, paraphyletic)[13] 

"†Acanthodii" ("spiny sharks", paraphyletic or polyphyletic)[14]  

Chondrichthyes

"†Acanthodii" ("spiny sharks", paraphyletic or polyphyletic) 

(cartilaginous fishes)
Euteleostomi/

"†Acanthodii" ("spiny sharks", paraphyletic or polyphyletic) 

Actinopterygii

Cladistia (bichirs, reedfish)  

Chondrostei (sturgeons, paddlefish) 

Neopterygii (includes Teleostei, 96% of living fish species) 

(ray‑finned fishes)
Sarcopterygii

†Onychodontiformes  

Actinistia (coelacanths)  

Rhipidistia

†Porolepiformes 

Dipnoi (lungfishes)  

Tetrapodomorpha/

†Rhizodontimorpha 

†Tristichopteridae 

†Tiktaalik 

Tetrapoda

†Ichthyostega 

crown-group tetrapods        

four‑limbed vertebrates
(Choanata)
(lobe‑finned fish)
Osteichthyes
(jawed vertebrates)
"Fishes"
Craniata

Taxonomy

 
Leedsichthys, of the subclass Actinopterygii, is the largest known fish, with estimates in 2005 putting its maximum size at 16 metres (52 ft).

Fishes are a paraphyletic group and for this reason, groups such as the class Pisces seen in older reference works are no longer used in formal classifications. Traditional classification divides fish into three extant classes, and with extinct forms sometimes classified within the tree, sometimes as their own classes:[15][16]

The above scheme is the one most commonly encountered in non-specialist and general works. Many of the above groups are paraphyletic, in that they have given rise to successive groups: Agnathans are ancestral to Chondrichthyes, who again have given rise to Acanthodiians, the ancestors of Osteichthyes. With the arrival of phylogenetic nomenclature, the fishes has been split up into a more detailed scheme, with the following major groups:

† – indicates extinct taxon
Some palaeontologists contend that because Conodonta are chordates, they are primitive fish. For a fuller treatment of this taxonomy, see the vertebrate article.

The position of hagfish in the phylum Chordata is not settled. Phylogenetic research in 1998 and 1999 supported the idea that the hagfish and the lampreys form a natural group, the Cyclostomata, that is a sister group of the Gnathostomata.[17][18]

The various fish groups account for more than half of vertebrate species. As of 2006,[19] there are almost 28,000 known extant species, of which almost 27,000 are bony fish, with 970 sharks, rays, and chimeras and about 108 hagfish and lampreys. A third of these species fall within the nine largest families; from largest to smallest, these families are Cyprinidae, Gobiidae, Cichlidae, Characidae, Loricariidae, Balitoridae, Serranidae, Labridae, and Scorpaenidae. About 64 families are monotypic, containing only one species. The final total of extant species may grow to exceed 32,500.[20] Each year, new species are discovered and scientifically described. As of 2016,[21] there are over 32,000 documented species of bony fish and over 1,100 species of cartilaginous fish. Species are lost through extinction (see biodiversity crisis). Recent examples are the Chinese paddlefish or the smooth handfish.

Diversity

Main article: Diversity of fish
 
A relative of the seahorses, the leafy seadragon's appendages allow it to camouflage (in the form of crypsis) with the surrounding seaweed.
 
The psychedelic mandarin dragonet is one of only two fish species where the blue colouring has been shown to be due to blue pigment containing chromatophores in the skin.[22]

The term "fish" most precisely describes any non-tetrapod craniate (i.e. an animal with a skull and in most cases a backbone) that has gills throughout life and whose limbs, if any, are in the shape of fins.[23] Unlike groupings such as birds or mammals, fish are not a single clade but a paraphyletic collection of taxa, including hagfishes, lampreys, sharks and rays, ray-finned fish, coelacanths, and lungfish.[24][25] Indeed, lungfish and coelacanths are closer relatives of tetrapods (such as mammals, birds, amphibians, etc.) than of other fish such as ray-finned fish or sharks, so the last common ancestor of all fish is also an ancestor to tetrapods. As paraphyletic groups are no longer recognised in modern systematic biology, the use of the term "fish" as a biological group must be avoided.

Many types of aquatic animals commonly referred to as "fish" are not fish in the sense given above; examples include shellfish, cuttlefish, starfish, crayfish and jellyfish. In earlier times, even biologists did not make a distinction – sixteenth century natural historians classified also seals, whales, amphibians, crocodiles, even hippopotamuses, as well as a host of aquatic invertebrates, as fish.[26] However, according to the definition above, all mammals, including cetaceans like whales and dolphins, are not fish. In some contexts, especially in aquaculture, the true fish are referred to as finfish (or fin fish) to distinguish them from these other animals.

A typical fish is ectothermic, has a streamlined body for rapid swimming, extracts oxygen from water using gills or uses an accessory breathing organ to breathe atmospheric oxygen, has two sets of paired fins, usually one or two (rarely three) dorsal fins, an anal fin, and a tail fin, has jaws, has skin that is usually covered with scales, and lays eggs.

Each criterion has exceptions. Tuna, swordfish, and some species of sharks show some warm-blooded adaptations – they can heat their bodies significantly above ambient water temperature.[24] Streamlining and swimming performance varies from fish such as tuna, salmon, and jacks that can cover 10–20 body-lengths per second to species such as eels and rays that swim no more than 0.5 body-lengths per second.[27] Many groups of freshwater fish extract oxygen from the air as well as from the water using a variety of different structures. Lungfish have paired lungs similar to those of tetrapods, gouramis have a structure called the labyrinth organ that performs a similar function, while many catfish, such as Corydoras extract oxygen via the intestine or stomach.[28] Body shape and the arrangement of the fins is highly variable, covering such seemingly un-fishlike forms as seahorses, pufferfish, anglerfish, and gulpers. Similarly, the surface of the skin may be naked (as in moray eels), or covered with scales of a variety of different types usually defined as placoid (typical of sharks and rays), cosmoid (fossil lungfish and coelacanths), ganoid (various fossil fish but also living gars and bichirs), cycloid, and ctenoid (these last two are found on most bony fish).[29] There are even fish that live mostly on land or lay their eggs on land near water.[30] Mudskippers feed and interact with one another on mudflats and go underwater to hide in their burrows.[31] A single undescribed species of Phreatobius has been called a true "land fish" as this worm-like catfish strictly lives among waterlogged leaf litter.[32][33] Many species live in underground lakes, underground rivers or aquifers and are popularly known as cavefish.[34]

Fish range in size from the huge 16-metre (52 ft) whale shark to the tiny 8-millimetre (0.3 in) stout infantfish.

Fish species diversity is roughly divided equally between marine (oceanic) and freshwater ecosystems. Coral reefs in the Indo-Pacific constitute the center of diversity for marine fishes, whereas continental freshwater fishes are most diverse in large river basins of tropical rainforests, especially the Amazon, Congo, and Mekong basins. More than 5,600 fish species inhabit Neotropical freshwaters alone, 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 contain more freshwater fish species than occur in all of Europe.[35]

The deepest living fish in the ocean so far found is the Mariana snailfish (Pseudoliparis swirei) which lives at deeps of 8,000 meters (26,200 feet) along the Mariana Trench near Guam.[36]

The diversity of living fish (finfish) is unevenly distributed among the various groups, with teleosts making up the bulk of living fishes (96%), and over 50% of all vertebrate species.[21] The following cladogram[37] shows the evolutionary relationships of all groups of living fishes (with their respective diversity[21]) and the four-limbed vertebrates (tetrapods).

 
Diversity of various groups of fish (and other vertebrates) through time
 
Lungfish are the closest living relatives of tetrapods (four-limbed vertebrates).
 
The bowfin Amia calva is the sole survivor of the halecomorph clade.
Vertebrates

Jawless fish   (118 living species: hagfish, lampreys)

Jawed vertebrates

Cartilaginous fishes   (>1,100 living species: sharks, rays, chimaeras)

Bony fishes
Lobe-fin fish
Rhipidistia

Tetrapoda   (>30,000 living species: amphibians, mammals, reptiles, birds)

Dipnoi   (6 living species: lungfish)

Actinistia   (2 living species: coelacanths)

Ray-fin fish

Cladistia   (14 living species: bichirs, reedfish)

Actinopteri

Chondrostei   (27 living species: sturgeons, paddlefish)

Neopterygii
Holostei

Ginglymodi   (7 living species: gars, alligator gars)

Halecomorphi   (1 living species: bowfin)

Teleostei   (>32,000 living species)

Anatomy and physiology

Further information: Fish anatomy and Fish physiology
 
Organs: 1. Liver, 2. Gas bladder, 3. Roe, 4. Pyloric caeca, 5. Stomach, 6. Intestine

Respiration

See also: Aquatic respiration

Gills

 
Tuna gills inside the head. The fish head is oriented snout-downwards, with the view looking towards the mouth.

Most fish exchange gases using gills on either side of the pharynx. Gills consist of threadlike structures called filaments. Each filament contains a capillary network that provides a large surface area for exchanging oxygen and carbon dioxide. Fish exchange gases by pulling oxygen-rich water through their mouths and pumping it over their gills. In some fish, capillary blood flows in the opposite direction to the water, causing countercurrent exchange. The gills push the oxygen-poor water out through openings in the sides of the pharynx. Some fish, like sharks and lampreys, possess multiple gill openings. However, bony fish have a single gill opening on each side. This opening is hidden beneath a protective bony cover called an operculum.

Juvenile bichirs have external gills, a very primitive feature that they share with larval amphibians.

Air breathing

Fish from multiple groups can live out of the water for extended periods. Amphibious fish such as the mudskipper can live and move about on land for up to several days,[dubious – discuss] or live in stagnant or otherwise oxygen-depleted water. Many such fish can breathe air via a variety of mechanisms. The skin of anguillid eels may absorb oxygen directly. The buccal cavity of the electric eel may breathe air. Catfish of the families Loricariidae, Callichthyidae, and Scoloplacidae absorb air through their digestive tracts.[38] Lungfish, with the exception of the Australian lungfish, and bichirs have paired lungs similar to those of tetrapods and must surface to gulp fresh air through the mouth and pass spent air out through the gills. Gar and bowfin have a vascularized swim bladder that functions in the same way. Loaches, trahiras, and many catfish breathe by passing air through the gut. Mudskippers breathe by absorbing oxygen across the skin (similar to frogs). A number of fish have evolved so-called accessory breathing organs that extract oxygen from the air. Labyrinth fish (such as gouramis and bettas) have a labyrinth organ above the gills that performs this function. A few other fish have structures resembling labyrinth organs in form and function, most notably snakeheads, pikeheads, and the Clariidae catfish family.

Breathing air is primarily of use to fish that inhabit shallow, seasonally variable waters where the water's oxygen concentration may seasonally decline. Fish dependent solely on dissolved oxygen, such as perch and cichlids, quickly suffocate, while air-breathers survive for much longer, in some cases in water that is little more than wet mud. At the extreme, some air-breathing fish are able to survive in damp burrows for weeks without water, entering a state of aestivation (summertime hibernation) until water returns.

Air breathing fish can be divided into obligate air breathers and facultative air breathers. Obligate air breathers, such as the African lungfish, must breathe air periodically or they suffocate. Facultative air breathers, such as the catfish Hypostomus plecostomus, only breathe air if they need to and will otherwise rely on their gills for oxygen. Most air breathing fish are facultative air breathers that avoid the energetic cost of rising to the surface and the fitness cost of exposure to surface predators.[38]

Circulation

 
Didactic model of a fish heart

Fish have a closed-loop circulatory system. The heart pumps the blood in a single loop throughout the body. In most fish, the heart consists of four parts, including two chambers and an entrance and exit.[39] The first part is the sinus venosus, a thin-walled sac that collects blood from the fish's veins before allowing it to flow to the second part, the atrium, which is a large muscular chamber. The atrium serves as a one-way antechamber, sends blood to the third part, ventricle. The ventricle is another thick-walled, muscular chamber and it pumps the blood, first to the fourth part, bulbus arteriosus, a large tube, and then out of the heart. The bulbus arteriosus connects to the aorta, through which blood flows to the gills for oxygenation.

Digestion

Jaws allow fish to eat a wide variety of food, including plants and other organisms. Fish ingest food through the mouth and break it down in the esophagus. In the stomach, food is further digested and, in many fish, processed in finger-shaped pouches called pyloric caeca, which secrete digestive enzymes and absorb nutrients. Organs such as the liver and pancreas add enzymes and various chemicals as the food moves through the digestive tract. The intestine completes the process of digestion and nutrient absorption.

Excretion

As with many aquatic animals, most fish release their nitrogenous wastes as ammonia. Some of the wastes diffuse through the gills. Blood wastes are filtered by the kidneys.

Saltwater fish tend to lose water because of osmosis. Their kidneys return water to the body. The reverse happens in freshwater fish: they tend to gain water osmotically. Their kidneys produce dilute urine for excretion. Some fish have specially adapted kidneys that vary in function, allowing them to move from freshwater to saltwater.

Scales

Main article: Fish scale

The scales of fish originate from the mesoderm (skin); they may be similar in structure to teeth.

Sensory and nervous system

 
Dorsal view of the brain of the rainbow trout

Central nervous system

Fish typically have quite small brains relative to body size compared with other vertebrates, typically one-fifteenth the brain mass of a similarly sized bird or mammal.[40] However, some fish have relatively large brains, most notably mormyrids and sharks, which have brains about as massive relative to body weight as birds and marsupials.[41]

Fish brains are divided into several regions. At the front are the olfactory lobes, a pair of structures that receive and process signals from the nostrils via the two olfactory nerves.[40] The olfactory lobes are very large in fish that hunt primarily by smell, such as hagfish, sharks, and catfish. Behind the olfactory lobes is the two-lobed telencephalon, the structural equivalent to the cerebrum in higher vertebrates. In fish the telencephalon is concerned mostly with olfaction.[40] Together these structures form the forebrain.

Connecting the forebrain to the midbrain is the diencephalon (in the diagram, this structure is below the optic lobes and consequently not visible). The diencephalon performs functions associated with hormones and homeostasis.[40] The pineal body lies just above the diencephalon. This structure detects light, maintains circadian rhythms, and controls color changes.[40]

The midbrain (or mesencephalon) contains the two optic lobes. These are very large in species that hunt by sight, such as rainbow trout and cichlids.[40]

The hindbrain (or metencephalon) is particularly involved in swimming and balance.[40] The cerebellum is a single-lobed structure that is typically the biggest part of the brain.[40] Hagfish and lampreys have relatively small cerebellae, while the mormyrid cerebellum is massive and apparently involved in their electrical sense.[40]

The brain stem (or myelencephalon) is the brain's posterior.[40] As well as controlling some muscles and body organs, in bony fish at least, the brain stem governs respiration and osmoregulation.[40]

Sense organs

Main article: Sensory systems in fish

Most fish possess highly developed sense organs. Nearly all daylight fish have color vision that is at least as good as a human's (see vision in fishes). Many fish also have chemoreceptors that are responsible for extraordinary senses of taste and smell. Although they have ears, many fish may not hear very well. Most fish have sensitive receptors that form the lateral line system, which detects gentle currents and vibrations, and senses the motion of nearby fish and prey.[42] The sense information obtained from the lateral line system can be considered both a sense of touch and hearing. Blind cave fish navigate almost entirely through the sensations from their lateral line system.[43] Some fish, such as catfish and sharks, have the ampullae of Lorenzini, electroreceptors that detect weak electric currents on the order of millivolt.[44] Other fish, like the South American electric fishes Gymnotiformes, can produce weak electric currents, which they use in navigation and social communication.

Fish orient themselves using landmarks and may use mental maps based on multiple landmarks or symbols. Fish behavior in mazes reveals that they possess spatial memory and visual discrimination.[45]

Vision

Main article: Vision in fishes

Vision is an important sensory system for most species of fish. Fish eyes are similar to those of terrestrial vertebrates like birds and mammals, but have a more spherical lens. Their retinas generally 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 light. Amongst jawless fish, the lamprey has well-developed eyes, while the hagfish has only primitive eyespots.[46] Fish vision shows adaptation to their visual environment, for example deep sea fishes have eyes suited to the dark environment.

Hearing

See also: Hearing in fish

Hearing is an important sensory system for most species of fish. Fish sense sound using their lateral lines and their ears.

Cognition

Further information: Fish intelligence

New research has expanded preconceptions about the cognitive capacities of fish. For example, manta rays have exhibited behavior linked to self-awareness in mirror test cases. Placed in front of a mirror, individual rays engaged in contingency testing, that is, repetitive behavior aiming to check whether their reflection's behavior mimics their body movement.[47]

Wrasses have also passed the mirror test in a 2018 scientific study.[48][49]

Cases of tool use have also been noticed, notably in the Choerodon family, in archerfish and Atlantic cod.[50]

Capacity for pain

Further information: Pain in fish

Experiments done by William Tavolga provide evidence that fish have pain and fear responses. For instance, in Tavolga's experiments, toadfish grunted when electrically shocked and over time they came to grunt at the mere sight of an electrode.[51]

In 2003, Scottish scientists at the University of Edinburgh and the Roslin Institute concluded that rainbow trout exhibit behaviors often associated with pain in other animals. Bee venom and acetic acid injected into the lips resulted in fish rocking their bodies and rubbing their lips along the sides and floors of their tanks, which the researchers concluded were attempts to relieve pain, similar to what mammals would do.[52][53] Neurons fired in a pattern resembling human neuronal patterns.[53]

Professor James D. Rose of the University of Wyoming claimed the study was flawed since it did not provide proof that fish possess "conscious awareness, particularly a kind of awareness that is meaningfully like ours".[54] Rose argues that since fish brains are so different from human brains, fish are probably not conscious in the manner humans are, so that reactions similar to human reactions to pain instead have other causes. Rose had published a study a year earlier arguing that fish cannot feel pain because their brains lack a neocortex.[55] However, animal behaviorist Temple Grandin argues that fish could still have consciousness without a neocortex because "different species can use different brain structures and systems to handle the same functions."[53]

Animal welfare advocates raise concerns about the possible suffering of fish caused by angling. Some countries, such as Germany, have banned specific types of fishing, and the British RSPCA now formally prosecutes individuals who are cruel to fish.[56]

Emotion

In 2019, scientists have shown that members of the monogamous species Amatitlania siquia exhibit pessimistic behavior when they are prevented from being with their partner.[57]

Muscular system

Main article: Fish locomotion
 
The anatomy of Lampanyctodes hectoris (1) operculum (gill cover), (2) lateral line, (3) dorsal fin, (4) fat fin, (5) caudal peduncle, (6) caudal fin, (7) anal fin, (8) photophores, (9) pelvic fins (paired), (10) pectoral fins (paired)
 
Swim bladder of a rudd (Scardinius erythrophthalmus)

Most fish move by alternately contracting paired sets of muscles on either side of the backbone. These contractions form S-shaped curves that move down the body. As each curve reaches the back fin, backward force is applied to the water, and in conjunction with the fins, moves the fish forward. The fish's fins function like an airplane's flaps. Fins also increase the tail's surface area, increasing speed. The streamlined body of the fish decreases the amount of friction from the water. Since body tissue is denser than water, fish must compensate for the difference or they will sink. Many bony fish have an internal organ called a swim bladder that adjusts their buoyancy through manipulation of gases.

Endothermy

Although most fish are exclusively ectothermic, there are exceptions. The only known bony fishes (infraclass Teleostei) that exhibit endothermy are in the suborder Scombroidei – which includes the billfishes, tunas, and the butterfly kingfish, a basal species of mackerel[58] – and also the opah. The opah, a lampriform, was demonstrated in 2015 to use "whole-body endothermy", generating heat with its swimming muscles to warm its body while countercurrent exchange (as in respiration) minimizes heat loss.[59] It is able to actively hunt prey such as squid and swim for long distances due to the ability to warm its entire body, including its heart,[60] which is a trait typically found in only mammals and birds (in the form of homeothermy). In the cartilaginous fishes (class Chondrichthyes), sharks of the families Lamnidae (porbeagle, mackerel, salmon, and great white sharks) and Alopiidae (thresher sharks) exhibit endothermy. The degree of endothermy varies from the billfishes, which warm only their eyes and brain, to the bluefin tuna and the porbeagle shark, which maintain body temperatures in excess of 20 °C (68 °F) above ambient water temperatures.[58]

Endothermy, though metabolically costly, is thought to provide advantages such as increased muscle strength, higher rates of central nervous system processing, and higher rates of digestion.

Reproductive system

Further information: Fish reproduction and Spawn (biology)
 
Ovary of fish (Corumbatá)

Fish reproductive organs include testicles and ovaries. In most species, gonads are paired organs of similar size, which can be partially or totally fused.[61] There may also be a range of secondary organs that increase reproductive fitness.

In terms of spermatogonia distribution, the structure of teleosts testes has two types: in the most common, spermatogonia occur all along the seminiferous tubules, while in atherinomorph fish they are confined to the distal portion of these structures. Fish can present cystic or semi-cystic spermatogenesis in relation to the release phase of germ cells in cysts to the seminiferous tubules lumen.[61]

Fish ovaries may be of three types: gymnovarian, secondary gymnovarian or cystovarian. In the first type, the oocytes are released directly into the coelomic cavity and then enter the ostium, then through the oviduct and are eliminated. Secondary gymnovarian ovaries shed ova into the coelom from which they go directly into the oviduct. In the third type, the oocytes are conveyed to the exterior through the oviduct.[62] Gymnovaries are the primitive condition found in lungfish, sturgeon, and bowfin. Cystovaries characterize most teleosts, where the ovary lumen has continuity with the oviduct.[61] Secondary gymnovaries are found in salmonids and a few other teleosts.

Oogonia development in teleosts fish varies according to the group, and the determination of oogenesis dynamics allows the understanding of maturation and fertilization processes. Changes in the nucleus, ooplasm, and the surrounding layers characterize the oocyte maturation process.[61]

Postovulatory follicles are structures formed after oocyte release; they do not have endocrine function, present a wide irregular lumen, and are rapidly reabsorbed in a process involving the apoptosis of follicular cells. A degenerative process called follicular atresia reabsorbs vitellogenic oocytes not spawned. This process can also occur, but less frequently, in oocytes in other development stages.[61]

Some fish, like the California sheephead, are hermaphrodites, having both testes and ovaries either at different phases in their life cycle or, as in hamlets, have them simultaneously.

Over 97% of all known fish are oviparous,[63] that is, the eggs develop outside the mother's body. Examples of oviparous fish include salmon, goldfish, cichlids, tuna, and eels. In the majority of these species, fertilisation takes place outside the mother's body, with the male and female fish shedding their gametes into the surrounding water. However, a few oviparous fish practice internal fertilization, with the male using some sort of intromittent organ to deliver sperm into the genital opening of the female, most notably the oviparous sharks, such as the horn shark, and oviparous rays, such as skates. In these cases, the male is equipped with a pair of modified pelvic fins known as claspers.

Marine fish can produce high numbers of eggs which are often released into the open water column. The eggs have an average diameter of 1 millimetre (0.04 in).

The newly hatched young of oviparous fish are called larvae. They are usually poorly formed, carry a large yolk sac (for nourishment), and are very different in appearance from juvenile and adult specimens. The larval period in oviparous fish is relatively short (usually only several weeks), and larvae rapidly grow and change appearance and structure (a process termed metamorphosis) to become juveniles. During this transition larvae must switch from their yolk sac to feeding on zooplankton prey, a process which depends on typically inadequate zooplankton density, starving many larvae.

In ovoviviparous fish the eggs develop inside the mother's body after internal fertilization but receive little or no nourishment directly from the mother, depending instead on the yolk. Each embryo develops in its own egg. Familiar examples of ovoviviparous fish include guppies, angel sharks, and coelacanths.

Some species of fish are viviparous. In such species the mother retains the eggs and nourishes the embryos. Typically, viviparous fish have a structure analogous to the placenta seen in mammals connecting the mother's blood supply with that of the embryo. Examples of viviparous fish include the surf-perches, splitfins, and lemon shark. Some viviparous fish exhibit oophagy, in which the developing embryos eat other eggs produced by the mother. This has been observed primarily among sharks, such as the shortfin mako and porbeagle, but is known for a few bony fish as well, such as the halfbeak Nomorhamphus ebrardtii.[64] Intrauterine cannibalism is an even more unusual mode of vivipary, in which the largest embryos eat weaker and smaller siblings. This behavior is also most commonly found among sharks, such as the grey nurse shark, but has also been reported for Nomorhamphus ebrardtii.[64]

Aquarists commonly refer to ovoviviparous and viviparous fish as livebearers.

Acoustic communication

See also: Acoustic communication in aquatic animals

Acoustic communication in fish involves the transmission of acoustic signals from one individual of a species to another. The production of sounds as a means of communication among fish is most often used in the context of feeding, aggression or courtship behaviour.[3] The sounds emitted can vary depending on the species and stimulus involved. Fish can produce either stridulatory sounds by moving components of the skeletal system, or can produce non-stridulatory sounds by manipulating specialized organs such as the swimbladder.[65]

Stridulatory

 
French grunts – Haemulon flavolineatum

There are some species of fish that can produce sounds by rubbing or grinding their bones together. These noises produced by bone-on-bone interactions are known as 'stridulatory sounds'.[65]

An example of this is seen in Haemulon flavolineatum, a species commonly referred to as the 'French grunt fish', as it produces a grunting noise by grinding its teeth together.[65] This behaviour is most pronounced when the H. flavolineatum is in distress situations.[65] The grunts produced by this species of fishes generate a frequency of approximately 700 Hz, and last approximately 47 milliseconds.[65] The H. flavolineatum does not emit sounds with frequencies greater than 1000 Hz, and does not detect sounds that have frequencies greater than 1050 Hz.[65]

In a study conducted by Oliveira et al. (2014), the longsnout seahorse, Hippocampus reidi, was recorded producing two different categories of sounds; 'clicks' and 'growls'. The sounds emitted by the H. reidi are accomplished by rubbing their coronet bone across the grooved section of their neurocranium.[66] 'Clicking' sounds were found to be primarily produced during courtship and feeding, and the frequencies of clicks were within the range of 50 Hz-800 Hz.[67] The frequencies were noted to be on the higher end of the range during spawning periods, when the female and male fishes were less than fifteen centimeters apart.[67] Growl sounds were produced when the H. reidi encountered stressful situations, such as handling by researchers.[67] The 'growl' sounds consist of a series of sound pulses and are emitted simultaneously with body vibrations.[67]

Non-stridulatory

 
Oyster toadfish

Some fish species create noise by engaging specialized muscles that contract and cause swimbladder vibrations.

Oyster toadfish produce loud grunting sounds by contracting muscles located along the sides of their swim bladder, known as sonic muscles [68] Female and male toadfishes emit short-duration grunts, often as a fright response.[69] In addition to short-duration grunts, male toadfishes produce "boat whistle calls".[70] These calls are longer in duration, lower in frequency, and are primarily used to attract mates.[70] The sounds emitted by the O. tao have frequency range of 140 Hz to 260 Hz.[70] The frequencies of the calls depend on the rate at which the sonic muscles contract.[71][68]

The red drum, Sciaenops ocellatus, produces drumming sounds by vibrating its swimbladder.[72] Vibrations are caused by the rapid contraction of sonic muscles that surround the dorsal aspect of the swimbladder.[72] These vibrations result in repeated sounds with frequencies that range from 100 to >200 Hz.[72] The S. ocellatus can produce different calls depending on the stimuli involved.[72] The sounds created in courtship situations are different from those made during distressing events such as predatorial attacks.[72] Unlike the males of the S. ocellatus species, the females of this species do not produce sounds and lack sound-producing (sonic) muscles.[72]

Diseases

Main article: Fish diseases and parasites

Like other animals, fish suffer from diseases and parasites. To prevent disease they have a variety of defenses. Non-specific defenses include the skin and scales, as well as the mucus layer secreted by the epidermis that traps and inhibits the growth of microorganisms. If pathogens breach these defenses, fish can develop an inflammatory response that increases blood flow to the infected region and delivers white blood cells that attempt to destroy pathogens. Specific defenses respond to particular pathogens recognised by the fish's body, i.e., an immune response.[73] In recent years, vaccines have become widely used in aquaculture and also with ornamental fish, for example furunculosis vaccines in farmed salmon and koi herpes virus in koi.[74][75]

Some species use cleaner fish to remove external parasites. The best known of these are the bluestreak cleaner wrasses of the genus Labroides found on coral reefs in the Indian and Pacific oceans. These small fish maintain so-called "cleaning stations" where other fish congregate and perform specific movements to attract the attention of the cleaners.[76] Cleaning behaviors have been observed in a number of fish groups, including an interesting case between two cichlids of the same genus, Etroplus maculatus, the cleaner, and the much larger Etroplus suratensis.[77]

Immune system

Immune organs vary by type of fish.[78] In the jawless fish (lampreys and hagfish), true lymphoid organs are absent. These fish rely on regions of lymphoid tissue within other organs to produce immune cells. For example, erythrocytes, macrophages and plasma cells are produced in the anterior kidney (or pronephros) and some areas of the gut (where granulocytes mature.) They resemble primitive bone marrow in hagfish. Cartilaginous fish (sharks and rays) have a more advanced immune system. They have three specialized organs that are unique to Chondrichthyes; the epigonal organs (lymphoid tissue similar to mammalian bone) that surround the gonads, the Leydig's organ within the walls of their esophagus, and a spiral valve in their intestine. These organs house typical immune cells (granulocytes, lymphocytes and plasma cells). They also possess an identifiable thymus and a well-developed spleen (their most important immune organ) where various lymphocytes, 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 meninges (membranes surrounding the central nervous system.) Their heart is frequently covered with tissue that contains lymphocytes, reticular cells and a small number of macrophages. The chondrostean kidney is an important hemopoietic organ; where erythrocytes, granulocytes, lymphocytes and macrophages develop.

Like chondrostean fish, the major immune tissues of bony fish (or teleostei) include the kidney (especially the anterior kidney), which houses many different immune cells.[79] In addition, teleost fish possess a thymus, spleen and scattered immune areas within mucosal tissues (e.g. in the skin, gills, gut and gonads). Much like the mammalian immune system, teleost erythrocytes, neutrophils and granulocytes are believed to reside in the spleen whereas lymphocytes are the major cell type found in the thymus.[80][81] In 2006, a lymphatic system similar to that in mammals was described in one species of teleost fish, the zebrafish. Although not confirmed as yet, this system presumably will be where naive (unstimulated) T cells accumulate while waiting to encounter an antigen.[82]

B and T lymphocytes bearing immunoglobulins and T cell receptors, respectively, are found in all jawed fishes. Indeed, the adaptive immune system as a whole evolved in an ancestor of all jawed vertebrates.[83]

Conservation

The 2006 IUCN Red List names 1,173 fish species that are threatened with extinction.[84] Included are species such as Atlantic cod,[85] Devil's Hole pupfish,[86] coelacanths,[87] and great white sharks.[88] Because fish live underwater they are more difficult to study than terrestrial animals and plants, and information about fish populations is often lacking. However, freshwater fish seem particularly threatened because they often live in relatively small water bodies. For example, the Devil's Hole pupfish occupies only a single 3 by 6 metres (10 by 20 ft) pool.[89]

Overfishing

 
Whale sharks, the largest species of fish, are classified as endangered.
Main article: Overfishing

Overfishing is a major threat to edible fish such as cod and tuna.[90][91] Overfishing eventually causes population (known as stock) collapse because the survivors cannot produce enough young to replace those removed. Such commercial extinction does not mean that the species is extinct, merely that it can no longer sustain a fishery.

One well-studied example of fishery collapse is the Pacific sardine Sadinops sagax caerulues fishery off the California coast. From a 1937 peak of 790,000 long tons (800,000 t) the catch steadily declined to only 24,000 long tons (24,000 t) in 1968, after which the fishery was no longer economically viable.[92]

The main tension between fisheries science and the fishing industry is that the two groups have different views on the resiliency of fisheries to intensive fishing. In places such as Scotland, Newfoundland, and Alaska the fishing industry is a major employer, so governments are predisposed to support it.[93][94] On the other hand, scientists and conservationists push for stringent protection, warning that many stocks could be wiped out within fifty years.[95][96]

Habitat destruction

See also: Environmental impact of fishing

A key stress on both freshwater and marine ecosystems is habitat degradation including water pollution, the building of dams, removal of water for use by humans, and the introduction of exotic species.[97] An example of a fish that has become endangered because of habitat change is the pallid sturgeon, a North American freshwater fish that lives in rivers damaged by human activity.[98]

Exotic species

Introduction of non-native species occurs in many habitats. A notable case in point is the Mediterranean Sea which has become a major ‘hotspot’ of exotic invaders since the opening of the Suez Canal in 1869. Since that time a thousand marine species of all sorts - fishes, seaweeds, invertebrates - originating from the Red Sea and more broadly from the Indo-Pacific have crossed the Canal from south to north to settle in the eastern Mediterranean Basin. Nowadays many of these tropical migrants, also called Lessepsian species, have extended their range towards the west, obviously favoured by the general warming of the Mediterranean. The resulting change in biodiversity is without precedent in human memory and is accelerating: a long-term cross-Basin survey engaged by the Mediterranean Science Commission recently documented [99] that in just twenty years, from 2001 till 2021, no less than 107 alien fish species have reached the Mediterranean from both the tropical Atlantic and the Red Sea, which is more than the total recorded during the whole 130 preceding years.

Another mode of introduction for marine species is transport across thousands of kms on ship hulls or in ballast waters. Examples abound of marine organisms being transported in ballast water, among them the invasive comb jelly Mnemiopsis leidyi, the dangerous bacterium Vibrio cholerae, or the fouling zebra mussel. The Mediterranean and Black Seas, with their high volume shipping from exotic harbors, are particularly impacted by this problem.[100]

Deliberate introductions of species with market potential are another frequent vector: one of the best studied examples is the introduction of the Nile perch into Lake Victoria in the 1960s. Nile perch gradually exterminated the lake's 500 endemic cichlid species. Some of them now survive in captive breeding programmes, but others are probably extinct.[101] Carp, snakeheads,[102] tilapia, European perch, brown trout, rainbow trout, and sea lampreys are other examples of fish that have caused problems by being introduced into alien environments.

Importance to humans

Economic

Main articles: Commercial fishing, Fishing industry, Aquaculture, and Fish farming
 
These fish-farming ponds were created as a cooperative project in a rural village.
 
Fish counter display at the Oulu Market Hall in Oulu, Finland.

Throughout history, humans have used fish as a food source for dietary protein. Historically and today, most fish harvested for human consumption has come by means of catching wild fish. However, fish farming, which has been practiced since about 3,500 BCE in ancient China,[103] is becoming increasingly important in many nations. Overall, about one-sixth of the world's protein is estimated to be provided by fish.[104] That proportion is considerably elevated in some developing nations and regions heavily dependent on seafood. In a similar manner, fish have been tied to primary industry and associated food, feed, pharmaceutical production and service industries.

Catching fish for the purpose of food or sport is known as fishing, while the organized effort by humans to catch fish is called a fishery (which also describes the area where such enterprise operates). Fisheries are a huge global business and provide income for millions of people.[104] The annual yield from all fisheries worldwide is about 154 million tons,[105] with popular species including herring, cod, anchovy, tuna, flounder, and salmon. However, the term fishery is broadly applied, and includes more organisms than just fish, such as mollusks and crustaceans, which are often collectively called "shellfish" when used as food.

Recreation

 
A Bengali fish vendor from Sylhet

Fishkeeping

Main article: Fishkeeping

Fish have been recognized as a source of beauty for almost as long as used for food, appearing in cave art, being raised as ornamental fish in ponds, and displayed in aquariums in homes, offices, or public settings.

Recreational fishing

Main articles: Recreational fishing, Angling, and Fishing tournament

Recreational fishing is fishing primarily for pleasure or competition; it can be contrasted with commercial fishing, which is fishing for profit, or artisanal fishing, which is fishing primarily for food. The most common form of recreational fishing is done with a rod, reel, line, hooks, and any one of a wide range of baits. Recreational fishing is particularly popular in North America and Europe and state, provincial, and federal government agencies actively management target fish species.[106][107] Angling is a method of fishing, specifically the practice of catching fish by means of an "angle" (hook). Anglers must select the right hook, cast accurately, and retrieve at the right speed while considering water and weather conditions, species, fish response, time of the day, and other factors.

Culture

Main article: Fish in culture
 
Avatar of Vishnu as a Matsya

Fish themes have symbolic significance in many religions. In ancient Mesopotamia, fish offerings were made to the gods from the very earliest times.[108] Fish were also a major symbol of Enki, the god of water.[108] Fish frequently appear as filling motifs in cylinder seals from the Old Babylonian (c. 1830 BC – c. 1531 BC) and Neo-Assyrian (911–609 BC) periods.[108] Starting during the Kassite Period (c. 1600 BC – c. 1155 BC) and lasting until the early Persian Period (550–30 BC), healers and exorcists dressed in ritual garb resembling the bodies of fish.[108] During the Seleucid Period (312–63 BC), the legendary Babylonian culture hero Oannes, described by Berossus, was said to have dressed in the skin of a fish.[108] Fish were sacred to the Syrian goddess Atargatis[109] and, during her festivals, only her priests were permitted to eat them.[109]

 
The ichthus is a Christian symbol of a fish signifying that the person who uses it is a Christian.[109][110]

In the Book of Jonah, a work of Jewish literature probably written in the fourth century BC, the central figure, a prophet named Jonah, is swallowed by a giant fish after being thrown overboard by the crew of the ship he is travelling on.[111][112][113] The fish later vomits Jonah out on shore after three days.[111][112][113] This book was later included as part of the Hebrew Bible, or Christian Old Testament,[114][115] and a version of the story it contains is summarized in Surah 37:139-148 of the Quran.[116] Early Christians used the ichthys, a symbol of a fish, to represent Jesus,[109][110] because the Greek word for fish, ΙΧΘΥΣ Ichthys, could be used as an acronym for "Ίησοῦς Χριστός, Θεοῦ Υἱός, Σωτήρ" (Iesous Christos, Theou Huios, Soter), meaning "Jesus Christ, Son of God, Saviour".[109][110] The gospels also refer to "fishers of men"[117] and feeding the multitude. In the dhamma of Buddhism, the fish symbolize happiness as they have complete freedom of movement in the water.

Among the deities said to take the form of a fish are Ika-Roa of the Polynesians, Dagon of various ancient Semitic peoples, the shark-gods of Hawaiʻi and Matsya of the Hindus. The astrological symbol Pisces is based on a constellation of the same name, but there is also a second fish constellation in the night sky, Piscis Austrinus.[118]

Fish feature prominently in art and literature, in movies such as Finding Nemo and books such as The Old Man and the Sea. Large fish, particularly sharks, have frequently been the subject of horror movies and thrillers, most notably the novel Jaws, which spawned a series of films of the same name that in turn inspired similar films or parodies such as Shark Tale and Snakehead Terror. Piranhas are shown in a similar light to sharks in films such as Piranha; however, contrary to popular belief, the red-bellied piranha is actually a generally timid scavenger species that is unlikely to harm humans.[119] Legends of half-human, half-fish mermaids have featured in folklore, including the stories of Hans Christian Andersen.

Terminology

"Fish" or "fishes"

Though often used interchangeably, in biology these words have different meanings. Fish is used as a singular noun, or as a plural to describe multiple individuals from a single species. Fishes is used to describe different species or species groups.[120][121][122] Thus a pond would be said to contain 120 fish if all were from a single species or 120 fishes if these included a mix of several species. The distinction is similar to that between people and peoples.

"True fish" or "finfish"

  • In biology, the term fish is most strictly used to describe any animal with a backbone, gills throughout life, and limbs (if any) in the shape of fins.[23] Many types of aquatic animals with common names ending in "fish" are not fish in this sense; examples include shellfish, cuttlefish, starfish, crayfish and jellyfish. In earlier times, even biologists did not make a distinction – sixteenth century natural historians classified also seals, whales, amphibians, crocodiles, even hippopotamuses, as well as a host of aquatic invertebrates, as fish.[26]
  • In fisheries, the term fish is used as a collective term, and includes mollusks, crustaceans and any aquatic animal which is harvested.[123]
  • The strict biological definition of a fish, above, is sometimes called a true fish. True fish are also referred to as finfish or fin fish to distinguish them from other aquatic life harvested in fisheries or aquaculture.

"Shoal" or "school"

Main article: Shoaling and schooling
 
These goldband fusiliers are schooling because their swimming is synchronised.

An assemblage of fish merely using some localised resource such as food or nesting sites is known simply as an aggregation. When fish come together in an interactive, social grouping, then they may be forming either a shoal or a school depending on the degree of organisation. A shoal is a loosely organised group where each fish swims and forages independently but is attracted to other members of the group and adjusts its behaviour, such as swimming speed, so that it remains close to the other members of the group. Schools of fish are much more tightly organised, synchronising their swimming so that all fish move at the same speed and in the same direction. Shoaling and schooling behaviour is believed to provide a variety of advantages.[124]

Examples:

  • Cichlids congregating at lekking sites form an aggregation.
  • Many minnows and characins form shoals.
  • Anchovies, herrings and silversides are classic examples of schooling fish.

The most common collective nouns for a group of fish in general are school and shoal. Both the words have evolved from the same common Dutch root 'schole' meaning a troop or crowd. While the words "school" and "shoal" have different meanings within biology, the distinctions are often ignored by non-specialists who treat the words as synonyms. Thus speakers of British English commonly use "shoal" to describe any grouping of fish, and speakers of American English commonly use "school" just as loosely.[125]

See also

Main article: Outline of fish
For a topical guide to sharks, see Outline of sharks.

Notes

  1. ^ Goldman, K.J. (1997). . Journal of Comparative Physiology. B Biochemical Systemic and Environmental Physiology. 167 (6): 423–429. doi:10.1007/s003600050092. S2CID 28082417. Archived from the original on 6 April 2012. Retrieved 12 October 2011.
  2. ^ Carey, F.G.; Lawson, K.D. (February 1973). "Temperature regulation in free-swimming bluefin tuna". Comparative Biochemistry and Physiology A. 44 (2): 375–392. doi:10.1016/0300-9629(73)90490-8. PMID 4145757.
  3. ^ a b Weinmann, S.R.; Black, A.N.; Richter, M. L.; Itzkowitz, M; Burger, R.M (February 2017). "Territorial vocalization in sympatric damselfish: acoustic characteristics and intruder discrimination". Bioacoustics. 27 (1): 87–102. doi:10.1080/09524622.2017.1286263. S2CID 89625932.
  4. ^ Yancey, PH; Gerringer, ME; Drazen, JC; Rowden, AA; Jamieson, A (2014). "Marine fish may be biochemically constrained from inhabiting the deepest ocean depths". Proc Natl Acad Sci U S A. 111 (12): 4461–4465. Bibcode:2014PNAS..111.4461Y. doi:10.1073/pnas.1322003111. PMC 3970477. PMID 24591588.
  5. ^ "FishBase Search". FishBase. March 2020. from the original on 3 March 2020. Retrieved 19 March 2020.
  6. ^ "Zoology" (PDF).
  7. ^ Greene, Harry W. (1 January 1998). "We are primates and we are fish: Teaching monophyletic organismal biology". Integrative Biology: Issues, News, and Reviews. 1 (3): 108–111. doi:10.1002/(sici)1520-6602(1998)1:3<108::aid-inbi5>3.0.co;2-t. ISSN 1520-6602.
  8. ^ "DWDS – Digitales Wörterbuch der deutschen Sprache". DWDS (in German). Retrieved 21 January 2023.
  9. ^ Winfred Philipp Lehmann, Helen-Jo J. Hewitt, Sigmund Feist, A Gothic etymological dictionary, 1986, s.v. fisks p. 118
  10. ^ "fish, n.1", OED Online, Oxford University Press, retrieved 21 January 2023
  11. ^ Carl Darling Buck, A Dictionary of Selected Synonyms in the Principal Indo-European Languages, 1949, s.v., section 3.65, p. 184
  12. ^ "Monster fish crushed opposition with strongest bite ever". Smh.com.au. 30 November 2006. from the original on 2 April 2013. Retrieved 26 February 2013.
  13. ^   Giles, Sam; Friedman, Matt; Brazeau, Martin D. (12 January 2015). "Osteichthyan-like cranial conditions in an Early Devonian stem gnathostome". Nature. 520 (7545): 82–85. Bibcode:2015Natur.520...82G. doi:10.1038/nature14065. ISSN 1476-4687. PMC 5536226. PMID 25581798.
  14. ^ Davis, S; Finarelli, J; Coates, M (2012). "Acanthodes and shark-like conditions in the last common ancestor of modern gnathostomes". Nature. 486 (7402): 247–250. Bibcode:2012Natur.486..247D. doi:10.1038/nature11080. PMID 22699617. S2CID 4304310.
  15. ^ Romer, A.S. & T.S. Parsons. 1977. The Vertebrate Body. 5th ed. Saunders, Philadelphia. (6th ed. 1985)
  16. ^ Benton, M.J. (1998) The quality of the fossil record of vertebrates. pp. 269–303, in Donovan, S.K. and Paul, C.R.C. (eds), The adequacy of the fossil record, Fig. 2. Wiley, New York, 312 pp.
  17. ^ Shigehiro Kuraku, Daisuke Hoshiyama, Kazutaka Katoh, Hiroshi Suga, Takashi Miyata (1999) Monophyly of Lampreys and Hagfishes Supported by Nuclear DNA–Coded Genes J Mol Evol (1999) 49:729–735
  18. ^ J. Mallatt, J. Sullivan (1998) 28S and 18S rDNA sequences support the monophyly of lampreys and hagfishes Molecular Biology and Evolution V 15, Issue 12, pp. 1706–1718
  19. ^ Nelson 2006, pp. 4–5.
  20. ^ Nelson 2006, p. 3.
  21. ^ a b c Nelson, Joseph, S. (2016). Fishes of the World. John Wiley & Sons, Inc. ISBN 978-1-118-34233-6.
  22. ^ Goda, M.; R. Fujii (2009). "Blue Chromatophores in Two Species of Callionymid Fish". Zoological Science. 12 (6): 811–813. doi:10.2108/zsj.12.811. S2CID 86385679.
  23. ^ a b Nelson 2006, p. 2.
  24. ^ a b Helfman, Collette & Facey 1997, p. 3.
  25. ^ Tree of life web project – Chordates 24 February 2007 at the Wayback Machine.
  26. ^ a b Cleveland P. Hickman Jr.; Larry S. Roberts; Allan L. Larson (2001). Integrated Principles of Zoology. McGraw-Hill Publishing Co. ISBN 978-0-07-290961-6.
  27. ^ Helfman, Collette & Facey 1997, p. 103.
  28. ^ Helfman, Collette & Facey 1997, pp. 53–57.
  29. ^ Helfman, Collette & Facey 1997, pp. 33–36.
  30. ^ Martin, K.L.M. (2014). Beach-Spawning Fishes: Reproduction in an Endangered Ecosystem. CRC Press. ISBN 978-1-4822-0797-2.
  31. ^ Froese, Rainer; Pauly, Daniel (eds.) (2006). "Periophthalmus barbarus" in FishBase. November 2006 version.
  32. ^ Planet Catfish. "Cat-eLog: Heptapteridae: Phreatobius: Phreatobius sp. (1)". Planet Catfish. from the original on 23 October 2006. Retrieved 26 November 2006.
  33. ^ Henderson, P.A.; Walker, I. (1990). "Spatial organization and population density of the fish community of the litter banks within a central Amazonian blackwater stream". Journal of Fish Biology. 37 (3): 401–411. doi:10.1111/j.1095-8649.1990.tb05871.x.
  34. ^ Aldemaro, R., ed. (2001). The Biology of Hypogean Fishes. Developments in environmental biology of fishes. Vol. 21. ISBN 978-1-4020-0076-8.
  35. ^ central3.to.gov.br https://central3.to.gov.br/arquivo/24/199. Retrieved 21 January 2023. {{cite web}}: Missing or empty |title= (help)
  36. ^ "There's a deeper fish in the sea". UW News. Retrieved 11 December 2020.
  37. ^ Friedman, Matt; Sallan, Lauren Cole (June 2012). "Five hundred million years of extinczion and recovery: A Phanerozoic survey of large-scale diversity patterns in fishes". Palaeontology. 55 (4): 707–742. doi:10.1111/j.1475-4983.2012.01165.x. S2CID 59423401.
  38. ^ a b Armbruster, Jonathan W. (1998). (PDF). Copeia. 1998 (3): 663–675. doi:10.2307/1447796. JSTOR 1447796. Archived from the original (PDF) on 26 March 2009. Retrieved 25 June 2009.
  39. ^ Setaro, John F. (1999). Circulatory System. Microsoft Encarta 99.
  40. ^ a b c d e f g h i j k Helfman, Collette & Facey 1997, pp. 48–49.
  41. ^ Helfman, Collette & Facey 1997, p. 191.
  42. ^ Orr, James (1999). Fish. Microsoft Encarta 99. ISBN 978-0-8114-2346-5.
  43. ^ Godfrey-Smith, Peter (10 November 2020). "Kingfish". Metazoa. New York: Farrar, Straus, and Giroux. ISBN 9780374207946.
  44. ^ Albert, J.S., and W.G.R. Crampton. 2005. Electroreception and electrogenesis. pp. 431–472 in The Physiology of Fishes, 3rd Edition. D.H. Evans and J.B. Claiborne (eds.). CRC Press.
  45. ^ Sciences, Journal of Undergraduate Life. (PDF). Archived from the original (PDF) on 6 July 2011. Retrieved 28 May 2009.
  46. ^ Campbell, Neil A.; Reece, Jane B. (2005). Biology (Seventh ed.). San Francisco: Benjamin Cummings.
  47. ^ Ari, Csilla; D’Agostino, Dominic P. (1 May 2016). "Contingency checking and self-directed behaviors in giant manta rays: Do elasmobranchs have self-awareness?". Journal of Ethology. 34 (2): 167–174. doi:10.1007/s10164-016-0462-z. ISSN 1439-5444. S2CID 254134775.
  48. ^ Kohda, Masanori; Hotta, Takashi; Takeyama, Tomohiro; Awata, Satoshi; Tanaka, Hirokazu; Asai, Jun-ya; Jordan, L. Alex (21 August 2018). "Cleaner wrasse pass the mark test. What are the implications for consciousness and self-awareness testing in animals?": 397067. doi:10.1101/397067. S2CID 91375693. {{cite journal}}: Cite journal requires |journal= (help)
  49. ^ "Scientists find some fish can 'recognise themselves' in mirror". the Guardian. 7 February 2019. Retrieved 21 January 2023.
  50. ^ Fishes Use Problem-Solving and Invent Tools- article at Scientific American 18 May 2020 at the Wayback Machine
  51. ^ Dunayer, Joan, "Fish: Sensitivity Beyond the Captor's Grasp," The Animals' Agenda, July/August 1991, pp. 12–18
  52. ^ Kirby, Alex (30 April 2003). "Fish do feel pain, scientists say". BBC News. from the original on 15 February 2009. Retrieved 4 January 2010.
  53. ^ a b c Grandin, Temple; Johnson, Catherine (2005). Animals in Translation. New York City: Scribner. pp. 183–184. ISBN 978-0-7432-4769-6.
  54. ^ (PDF). Archived from the original (PDF) on 8 June 2011. Retrieved 21 May 2011.
  55. ^ Rose, James D. (2002). . Archived from the original on 20 January 2013. Retrieved 27 September 2007.
  56. ^ Leake, Jonathan (14 March 2004). "Anglers to face RSPCA checks". The Sunday Times.
  57. ^ Laubu, Chloé; Louâpre, Philippe; Dechaume-Moncharmont, François-Xavier (2019). "Pair-bonding influences affective state in a monogamous fish species". Proc. R. Soc. B. 286 (1904). 20190760. doi:10.1098/rspb.2019.0760. PMC 6571461. PMID 31185864.
  58. ^ a b Block, BA; Finnerty, JR (1993). "Endothermy in fishes: a phylogenetic analysis of constraints, predispositions, and selection pressures" (PDF). Environmental Biology of Fishes. 40 (3): 283–302. doi:10.1007/BF00002518. S2CID 28644501.
  59. ^ Wegner, Nicholas C.; Snodgrass, Owyn E.; Dewar, Heidi; Hyde, John R. (15 May 2015). "Whole-body endothermy in a mesopelagic fish, the opah, Lampris guttatus". Science. 348 (6236): 786–789. Bibcode:2015Sci...348..786W. doi:10.1126/science.aaa8902. ISSN 0036-8075. PMID 25977549. S2CID 17412022.
  60. ^ . Southwest Fisheries Science Center. 12 May 2015. Archived from the original on 20 January 2018. Retrieved 7 March 2018.
  61. ^ a b c d e Guimaraes-Cruz, Rodrigo J.; dos Santos, José E.; Santos, Gilmar B. (July–September 2005). "Gonadal structure and gametogenesis of Loricaria lentiginosa Isbrücker (Pisces, Teleostei, Siluriformes)". Rev. Bras. Zool. 22 (3): 556–564. doi:10.1590/S0101-81752005000300005. ISSN 0101-8175.
  62. ^ Brito, M.F.G.; Bazzoli, N. (2003). "Reproduction of the surubim catfish (Pisces, Pimelodidae) in the São Francisco River, Pirapora Region, Minas Gerais, Brazil". Arquivo Brasileiro de Medicina Veterinária e Zootecnia. 55 (5): 624–633. doi:10.1590/S0102-09352003000500018. ISSN 0102-0935.
  63. ^ Peter Scott: Livebearing Fishes, p. 13. Tetra Press 1997. ISBN 1-56465-193-2
  64. ^ a b Meisner, A & Burns, J: Viviparity in the Halfbeak Genera Dermogenys and Nomorhamphus (Teleostei: Hemiramphidae)" Journal of Morphology 234, pp. 295–317, 1997
  65. ^ a b c d e f Bertucci, F.; Ruppé, L.; Wassenbergh, S.V.; Compère, P.; Parmentier, E. (29 October 2014). "New Insights into the Role of the Pharyngeal Jaw Apparatus in the Sound-Producing Mechanism of Haemulon Flavolineatum (Haemulidae)". Journal of Experimental Biology. 217 (21): 3862–3869. doi:10.1242/jeb.109025. PMID 25355850.
  66. ^ Colson, D.J.; Patek, S.N.; Brainerd, E.L.; Lewis, S.M. (February 1998). "Sound production during feeding in Hippocampus seahorses (Syngnathidae)". Environmental Biology of Fishes. 51 (2): 221–229. doi:10.1023/A:1007434714122. S2CID 207648816.
  67. ^ a b c d Oliveira, T.P.R.; Ladich, F.; Abed-Navandi, D.; Souto, A.S.; Rosa, I.L. (26 June 2014). "Sounds produced by the longsnout seahorse: a study of their structure and functions". Journal of Zoology. 294 (2): 114–121. doi:10.1111/jzo.12160.
  68. ^ a b Fine, L.F.; King, C.B.; Cameron, T.M. (16 October 2009). "Acoustical properties of the swimbladder in the oyster toadfish Opsanus tau". Journal of Experimental Biology. 212 (21): 3542–3552. doi:10.1242/jeb.033423. PMC 2762879. PMID 19837896.
  69. ^ Fine, M.L.; Waybright, T.D. (15 October 2015). "Grunt variation in the oyster toadfish Opsanus tau:effect of size and sex". PeerJ. 3 (1330): e1330. doi:10.7717/peerj.1330. PMC 4662586. PMID 26623178.
  70. ^ a b c Ricci, S. W.; Bohnenstiehl, D R.; Eggleston, D.B.; Kellogg, M.L.; Lyon, R.P. (8 August 2017). "Oyster toadfish (Opsanus tau) boatwhistle call detection and patterns within a large-scale oyster restoration site". PLOS ONE. 12 (8): e0182757. Bibcode:2017PLoSO..1282757R. doi:10.1371/journal.pone.0182757. PMC 5549733. PMID 28792543.
  71. ^ Skoglund, C.R. (1 August 1961). "Functional analysis of swimbladder muscles engaged in sound productivity of the toadfish". Journal of Cell Biology. 10 (4): 187–200. doi:10.1083/jcb.10.4.187. PMC 2225107. PMID 19866593.
  72. ^ a b c d e f Parmentier, E.; Tock, J.; Falguière, J.C.; Beauchaud, M. (22 May 2014). "Sound production in Sciaenops ocellatus: Preliminary study for the development of acoustic cues in aquaculture" (PDF). Aquaculture. 432: 204–211. doi:10.1016/j.aquaculture.2014.05.017.
  73. ^ Helfman, Collette & Facey 1997, pp. 95–96.
  74. ^ R.C. Cipriano; G.L. Bullock (2001). (PDF) (Report). Fish Disease Leaflet 66. U.S. Department of the Interior. Archived from the original (PDF) on 7 May 2009. Retrieved 3 July 2009.
  75. ^ Hartman, K.H.; et al. (2004). "Koi Herpes Virus (KHV) Disease: Fact Sheet VM-149" (PDF). University of Florida Institute of Food and Agricultural Sciences. (PDF) from the original on 6 February 2007.
  76. ^ Helfman, Collette & Facey 1997, p. 380.
  77. ^ Wyman, Richard L.; Ward, Jack A. (1972). "A Cleaning Symbiosis between the Cichlid Fishes Etroplus maculatus and Etroplus suratensis. I. Description and Possible Evolution". Copeia. 1972 (4): 834–838. doi:10.2307/1442742. JSTOR 1442742.
  78. ^ A.G. Zapata, A. Chiba and A. Vara. Cells and tissues of the immune system of fish. In: The Fish Immune System: Organism, Pathogen and Environment. Fish Immunology Series. (eds. G. Iwama and T.Nakanishi,), New York, Academic Press, 1996, pp. 1–55.
  79. ^ D.P. Anderson. Fish Immunology. (S.F. Snieszko and H.R. Axelrod, eds), Hong Kong: TFH Publications, Inc. Ltd., 1977.
  80. ^ Chilmonczyk, S. (1992). "The thymus in fish: development and possible function in the immune response". Annual Review of Fish Diseases. 2: 181–200. doi:10.1016/0959-8030(92)90063-4.
  81. ^ Hansen, J.D.; Zapata, A.G. (1998). "Lymphocyte development in fish and amphibians". Immunological Reviews. 166: 199–220. doi:10.1111/j.1600-065x.1998.tb01264.x. PMID 9914914. S2CID 7965762.
  82. ^ Küchler AM, Gjini E, Peterson-Maduro J, Cancilla B, Wolburg H, Schulte-Merker S (2006). "Development of the Zebrafish Lymphatic System Requires Vegfc Signaling" (PDF). Current Biology. 16 (12): 1244–1248. doi:10.1016/j.cub.2006.05.026. PMID 16782017.
  83. ^ Flajnik, M. F.; Kasahara, M. (2009). "Origin and evolution of the adaptive immune system: genetic events and selective pressures". Nature Reviews Genetics. 11 (1): 47–59. doi:10.1038/nrg2703. PMC 3805090. PMID 19997068.
  84. ^ . iucnredlist.org. Archived from the original on 30 June 2006. Retrieved 18 January 2006.
  85. ^ Sobel, J. (1996). "Gadus morhua". IUCN Red List of Threatened Species. 1996: e.T8784A12931575. doi:10.2305/IUCN.UK.1996.RLTS.T8784A12931575.en. Retrieved 11 November 2021.
  86. ^ NatureServe (2014). "Cyprinodon diabolis". IUCN Red List of Threatened Species. 2014: e.T6149A15362335. doi:10.2305/IUCN.UK.2014-3.RLTS.T6149A15362335.en. Retrieved 11 November 2021.
  87. ^ Musick, J.A. (2000). "Latimeria chalumnae". IUCN Red List of Threatened Species. 2000: e.T11375A3274618. doi:10.2305/IUCN.UK.2000.RLTS.T11375A3274618.en. Retrieved 11 November 2021.
  88. ^ Rigby, C.L.; Barreto, R.; Carlson, J.; Fernando, D.; Fordham, S.; Francis, M.P.; Herman, K.; Jabado, R.W.; Liu, K.M.; Lowe, C.G.; Marshall, A.; Pacoureau, N.; Romanov, E.; Sherley, R.B.; Winker, H. (2019). "Carcharodon carcharias". IUCN Red List of Threatened Species. 2019: e.T3855A2878674. Retrieved 19 December 2019.
  89. ^ Helfman, Collette & Facey 1997, pp. 449–450.
  90. ^ "Call to halt cod 'over-fishing'". BBC News. 5 January 2007. from the original on 17 January 2007. Retrieved 18 January 2006.
  91. ^ "Tuna groups tackle overfishing". BBC News. 26 January 2007. from the original on 21 January 2009. Retrieved 18 January 2006.
  92. ^ Helfman, Collette & Facey 1997, p. 462.
  93. ^ "UK 'must shield fishing industry'". BBC News. 3 November 2006. from the original on 30 November 2006. Retrieved 18 January 2006.
  94. ^ "EU fish quota deal hammered out". BBC News. 21 December 2006. from the original on 26 December 2006. Retrieved 18 January 2006.
  95. ^ "Ocean study predicts the collapse of all seafood fisheries by 2050". phys.org. from the original on 15 March 2007. Retrieved 13 January 2006.
  96. ^ . Archived from the original on 30 April 2007. Retrieved 18 January 2006.
  97. ^ Helfman, Collette & Facey 1997, p. 463.
  98. ^ . Archived from the original on 26 November 2005. Retrieved 18 March 2016.
  99. ^ "CIESM Online book store". ciesm.org. Retrieved 21 January 2023.
  100. ^ Briand, Frederic and Galil, Bella 2002. Alien marine organisms introduced by ships - An overview https://www.researchgate.net/publication/240305530
  101. ^ Spinney, Laura (4 August 2005). "The little fish fight back". The Guardian. London. Retrieved 18 January 2006.
  102. ^ "Stop That Fish!". The Washington Post. 3 July 2002. from the original on 3 November 2012. Retrieved 26 August 2007.
  103. ^ Spalding, Mark (11 July 2013). "Sustainable Ancient Aquaculture". National Geographic. from the original on 18 May 2015. Retrieved 13 August 2015.
  104. ^ a b Helfman, Gene S. (2007). Fish Conservation: A Guide to Understanding and Restoring Global Aquatic Biodiversity and Fishery Resources. Island Press. p. 11. ISBN 978-1-59726-760-1.
  105. ^ "World Review of Fisheries and Aquaculture" (PDF). fao.org. Food and Agriculture Organization of the United Nations. (PDF) from the original on 28 August 2015. Retrieved 13 August 2015.
  106. ^ Beard, T. Douglas, ed. (2011). The Angler in the Environment: Social, Economic, Biological, and Ethical Dimensions. Bethesda, MD: American Fisheries Society. p. 365. ISBN 978-1-934874-24-0.
  107. ^ Hickley, Phil; Tompkins, Helena, eds. (1998). Recreational Fisheries: Social, Economic and Management Aspects. Wiley-Blackwell. p. 328. ISBN 978-0-852-38248-6.
  108. ^ a b c d e Black, Jeremy; Green, Anthony (1992). Gods, Demons and Symbols of Ancient Mesopotamia: An Illustrated Dictionary. The British Museum Press. pp. 82–83. ISBN 978-0-7141-1705-8. from the original on 20 February 2018.
  109. ^ a b c d e Hyde, Walter Woodburn (2008) [1946]. Paganism to Christianity in the Roman Empire. Eugene, Oregon: Wipf and Stock Publishers. pp. 57–58. ISBN 978-1-60608-349-9.
  110. ^ a b c Coffman, Elesha (8 August 2008). "What is the origin of the Christian fish symbol?". Christianity Today. Retrieved 13 August 2015.
  111. ^ a b Sherwood, Yvonne (2000), A Biblical Text and Its Afterlives: The Survival of Jonah in Western Culture, Cambridge, England: Cambridge University Press, pp. 1–8, ISBN 978-0-521-79561-6
  112. ^ a b Ziolkowski, Jan M. (2007). Fairy Tales from Before Fairy Tales: The Medieval Latin Past of Wonderful Lies. Ann Arbor, Michigan: University of Michigan Press. p. 80. ISBN 978-0-472-03379-9.
  113. ^ a b Gaines, Janet Howe (2003). Forgiveness in a Wounded World: Jonah's Dilemma. Atlanta, Georgia: Society of Biblical Literature. pp. 8–9. ISBN 978-1-58983-077-6.
  114. ^ Band, Arnold J. (2003). Studies in Modern Jewish Literature. JPS Scholar of Distinction Series. Philadelphia, Pennsylvania: The Jewish Publication Society. pp. 106–107. ISBN 978-0-8276-0762-0.
  115. ^ Person, Raymond (1996). In Conversation with Jonah: Conversation Analysis, Literary Criticism, and the Book of Jonah. Sheffield, England: Sheffield Academic Press. p. 155. ISBN 978-1-85075-619-4.
  116. ^ Vicchio, Stephen J. (2008), Biblical Figures in the Islamic Faith, Eugene, Oregon: Wipf & Stock, p. 67, ISBN 978-1-55635-304-8
  117. ^ Matthew 4:19
  118. ^ "Piscis Austrinus". allthesky.com. The Deep Photographic Guide to the Constellations. from the original on 25 November 2015. Retrieved 1 November 2015.
  119. ^ Zollinger, Sue Anne (3 July 2009). "Piranha–Ferocious Fighter or Scavenging Softie?". A Moment of Science. Indiana Public Media. from the original on 17 October 2015. Retrieved 1 November 2015.
  120. ^ Pauly, Daniel (13 May 2004). "Fish(es)". Darwin's Fishes: An Encyclopedia of Ichthyology, Ecology, and Evolution. Cambridge University Press. p. 77. ISBN 978-1-139-45181-9. from the original on 8 February 2016.
  121. ^ Nelson, Joseph S.; Paetz, Martin Joseph (1992). (PDF). University of Alberta. p. 400. ISBN 978-0-88864-236-3. Archived from the original (PDF) on 7 April 2014.
  122. ^ Helfman, Collette & Facey 1997, p. 5.
  123. ^ "Fisheries". FAO TERM PORTAL. FAO.
  124. ^ Helfman, Collette & Facey 1997, p. 375.
  125. ^ Pitcher, T.J.; Parish, J.K. (1993). "Functions of shoaling behaviour in teleosts". In Pitcher, T.J. (ed.). Behaviour of teleost fishes. New York: Chapman and Hall. pp. 363–440. ISBN 9780412429309. from the original on 5 April 2017.

References

Further reading

  • Eschmeyer, William N.; Fong, Jon David (2013). "Catalog of Fishes". California Academy of Sciences.
  • Helfman, G.; Collette, B.; Facey, D.; Bowen, B. (2009). The Diversity of Fishes: Biology, Evolution, and Ecology (2nd ed.). Wiley-Blackwell. ISBN 978-1-4051-2494-2.
  • Moyle, Peter B. (1993) Fish: An Enthusiast's Guide University of California Press. ISBN 978-0-520-91665-4 – good lay text.
  • Moyle, Peter B.; Cech, Joseph J. (2003). Fishes, An Introduction to Ichthyology (5th ed.). Benjamin Cummings. ISBN 978-0-13-100847-2.
  • Scales, Helen (2018). Eye of the shoal: A Fishwatcher's Guide to Life, the Ocean and Everything. Bloomsbury Sigma. ISBN 978-1-4729-3684-4.
  • Shubin, Neil (2009). Your inner fish: A journey into the 3.5 billion year history of the human body. Vintage Books. ISBN 978-0-307-27745-9. UCTV interview 14 January 2021 at the Wayback Machine

External links

 
Wikimedia Commons has media related to Fish, Actinopterygii, Marine aquarium fish and Freshwater aquarium fish.
 
Wikiquote has quotations related to Fish.
 
Look up fish in Wiktionary, the free dictionary.
 
Wikispecies has information related to Actinopterygii.
 
Wikisource has the text of the 1911 Encyclopædia Britannica article "Fish".
  • ANGFA – Illustrated database of freshwater fishes of Australia and New Guinea
  • at the Wayback Machine (archived 30 November 2011) (in German)
  • FishBase online – Comprehensive database with information on over 29,000 fish species
  • Fisheries and Illinois Aquaculture Center – Data outlet for fisheries and aquaculture research center in the central US at archive.today (archived 15 December 2012)
  • Philippines Fishes – Database with thousands of Philippine Fishes photographed in natural habitat
  • at the Wayback Machine (archived 12 March 2008)
  • United Nation – Fisheries and Aquaculture Department: Fish and seafood utilization
  • – Digital collection of freshwater and marine fish images
  • Davenport, Charles B.; Ingersoll, Ernest (1905). "Fish" . New International Encyclopedia.

January 31, 2023
fish, fish, eaten, humans, food, superclass, containing, vast, majority, living, fish, osteichthyes, other, uses, disambiguation, aquatic, craniate, gill, bearing, animals, that, lack, limbs, with, digits, included, this, definition, living, hagfish, lampreys,. For fish as eaten by humans see Fish as food For the superclass containing the vast majority of living fish see Osteichthyes For other uses see Fish disambiguation Fish are aquatic craniate gill bearing animals that lack limbs with digits Included in this definition are the living hagfish lampreys and cartilaginous and bony fish as well as various extinct related groups Approximately 95 of living fish species are ray finned fish belonging to the class Actinopterygii with around 99 of those being teleosts FishTemporal range 535 0 Ma PreꞒ Ꞓ O S D C P T J K Pg N Middle Cambrian RecentGiant grouper swimming among schools of other fishHead on view of a red lionfishScientific classificationKingdom AnimaliaPhylum ChordataClade OlfactoresSubphylum VertebrataGroups includedJawless fish Armoured fish Spiny sharks Cartilaginous fish Bony fishRay finned fish Lobe finned fish dd Cladistically included but traditionally excluded taxaTetrapodsThe earliest organisms that can be classified as fish were soft bodied chordates that first appeared during the Cambrian period Although they lacked a true spine they possessed notochords which allowed them to be more agile than their invertebrate counterparts Fish would continue to evolve through the Paleozoic era diversifying into a wide variety of forms Many fish of the Paleozoic developed external armor that protected them from predators The first fish with jaws appeared in the Silurian period after which many such as sharks became formidable marine predators rather than just the prey of arthropods Most fish are ectothermic cold blooded allowing their body temperatures to vary as ambient temperatures change though some of the large active swimmers like white shark and tuna can hold a higher core temperature 1 2 Fish can acoustically communicate with each other most often in the context of feeding aggression or courtship 3 Fish are abundant in most bodies of water They can be found in nearly all aquatic environments from high mountain streams e g char and gudgeon to the abyssal and even hadal depths of the deepest oceans e g cusk eels and snailfish although no species has yet been documented in the deepest 25 of the ocean 4 With 34 300 described species fish exhibit greater species diversity than any other group of vertebrates 5 Fish are an important resource for humans worldwide especially as food Commercial and subsistence fishers hunt fish in wild fisheries or farm them in ponds or in cages in the ocean in aquaculture They are also caught by recreational fishers kept as pets raised by fishkeepers and exhibited in public aquaria Fish have had a role in culture through the ages serving as deities religious symbols and as the subjects of art books and movies Tetrapods amphibians reptiles birds and mammals emerged within lobe finned fishes so cladistically they are fish as well However traditionally fish pisces or ichthyes are rendered paraphyletic by excluding the tetrapods and are therefore not considered a formal taxonomic grouping in systematic biology unless it is used in the cladistic sense including tetrapods 6 7 although usually vertebrate is preferred and used for this purpose fish plus tetrapods instead Furthermore cetaceans although mammals have often been considered fish by various cultures and time periods Contents 1 Etymology 2 Evolution 2 1 Phylogeny 2 2 Taxonomy 2 3 Diversity 3 Anatomy and physiology 3 1 Respiration 3 1 1 Gills 3 1 2 Air breathing 3 2 Circulation 3 3 Digestion 3 4 Excretion 3 5 Scales 3 6 Sensory and nervous system 3 6 1 Central nervous system 3 6 2 Sense organs 3 6 3 Vision 3 6 4 Hearing 3 6 5 Cognition 3 6 6 Capacity for pain 3 6 7 Emotion 3 7 Muscular system 3 7 1 Endothermy 3 8 Reproductive system 4 Acoustic communication 4 1 Stridulatory 4 2 Non stridulatory 5 Diseases 5 1 Immune system 6 Conservation 6 1 Overfishing 6 2 Habitat destruction 6 3 Exotic species 7 Importance to humans 7 1 Economic 7 2 Recreation 7 2 1 Fishkeeping 7 2 2 Recreational fishing 7 3 Culture 8 Terminology 8 1 Fish or fishes 8 2 True fish or finfish 8 3 Shoal or school 9 See also 10 Notes 11 References 12 Further reading 13 External linksEtymologyThe word for fish in English and the other Germanic languages German Fisch Gothic fisks is inherited from Proto Germanic and is related to the Latin piscis and Old Irish iasc though the exact root is unknown some authorities reconstruct a Proto Indo European root peysk attested only in Italic Celtic and Germanic 8 9 10 11 The English word once had a much broader usage than its current biological meaning Names such as starfish jellyfish shellfish and cuttlefish attest to almost any fully aquatic animal including whales once being fish Correcting such names e g to sea star is an attempt to retroactively apply the current meaning of fish to words that were coined when it had a different meaning citation needed EvolutionMain article Evolution of fishFish as vertebrata developed as sister of the tunicata As the tetrapods emerged deep within the fishes group as sister of the lungfish characteristics of fish are typically shared by tetrapods including having vertebrae and a cranium Dunkleosteus was a gigantic 10 metre 33 ft long prehistoric fish of class Placodermi Lower jaw of the placoderm Eastmanosteus pustulosus showing the shearing structures teeth on its oral surface from the Devonian of Wisconsin Early fish from the fossil record are represented by a group of small jawless armored fish known as ostracoderms Jawless fish lineages are mostly extinct An extant clade the lampreys may approximate ancient pre jawed fish The first jaws are found in Placodermi fossils They lacked distinct teeth having instead the oral surfaces of their jaw plates modified to serve the various purposes of teeth The diversity of jawed vertebrates may indicate the evolutionary advantage of a jawed mouth It is unclear if the advantage of a hinged jaw is greater biting force improved respiration or a combination of factors Fish may have evolved from a creature similar to a coral like sea squirt whose larvae resemble primitive fish in important ways The first ancestors of fish may have kept the larval form into adulthood as some sea squirts do today Phylogeny Fishes are a paraphyletic group that is any clade containing all fish also contains the tetrapods which are not fish though they include fish shaped forms such as Whales and Dolphins or the extinct ichthyosaurs which acquired a fish like body shape due to secondary aquatic adaptation see evolution of cetaceans The following cladogram shows clades some with some without extant relatives that are traditionally considered as fishes cyan line and the tetrapods four limbed vertebrates which are mostly terrestrial Extinct groups are marked with a dagger Vertebrata Agnatha Hyperoartia lampreys Myxini hagfish Cyclostomes Euconodonta Pteraspidomorphi Thelodonti Anaspida Galeaspida Pituriaspida Osteostraci Gnathostomata Placodermi armoured fishes paraphyletic 13 Acanthodii spiny sharks paraphyletic or polyphyletic 14 Chondrichthyes Acanthodii spiny sharks paraphyletic or polyphyletic Holocephali ratfish Euselachii sharks rays cartilaginous fishes Euteleostomi Acanthodii spiny sharks paraphyletic or polyphyletic Actinopterygii Cladistia bichirs reedfish Chondrostei sturgeons paddlefish Neopterygii includes Teleostei 96 of living fish species ray finned fishes Sarcopterygii Onychodontiformes Actinistia coelacanths Rhipidistia Porolepiformes Dipnoi lungfishes Tetrapodomorpha Rhizodontimorpha Tristichopteridae Tiktaalik Tetrapoda Ichthyostega crown group tetrapods four limbed vertebrates Choanata lobe finned fish Osteichthyes jawed vertebrates Fishes CraniataTaxonomy Leedsichthys of the subclass Actinopterygii is the largest known fish with estimates in 2005 putting its maximum size at 16 metres 52 ft Fishes are a paraphyletic group and for this reason groups such as the class Pisces seen in older reference works are no longer used in formal classifications Traditional classification divides fish into three extant classes and with extinct forms sometimes classified within the tree sometimes as their own classes 15 16 Class Agnatha jawless fish Subclass Cyclostomata hagfish and lampreys Subclass Ostracodermi armoured jawless fish Class Chondrichthyes cartilaginous fish Subclass Elasmobranchii sharks and rays Subclass Holocephali chimaeras and extinct relatives Class Placodermi armoured fish Class Acanthodii spiny sharks sometimes classified under Actinopterygii Superclass Osteichthyes bony fish Class Actinopterygii ray finned fishes Clade Sarcopterygii lobe finned fishes ancestors of tetrapods The above scheme is the one most commonly encountered in non specialist and general works Many of the above groups are paraphyletic in that they have given rise to successive groups Agnathans are ancestral to Chondrichthyes who again have given rise to Acanthodiians the ancestors of Osteichthyes With the arrival of phylogenetic nomenclature the fishes has been split up into a more detailed scheme with the following major groups Class Myxini hagfish Class Pteraspidomorphi early jawless fish Class Thelodonti Class Anaspida Class Petromyzontida or Hyperoartia Petromyzontidae lampreys Class Conodonta conodonts Class Cephalaspidomorphi early jawless fish unranked Galeaspida unranked Pituriaspida unranked Osteostraci Infraphylum Gnathostomata jawed vertebrates Class Placodermi armoured fish Class Chondrichthyes cartilaginous fish Class Acanthodii spiny sharks Superclass Osteichthyes bony fish Class Actinopterygii ray finned fish Subclass Chondrostei Order Acipenseriformes sturgeons and paddlefishes Order Polypteriformes reedfishes and bichirs Subclass Neopterygii Infraclass Holostei gars and bowfins Infraclass Teleostei many orders of common fish Class Sarcopterygii lobe finned fish Subclass Actinistia coelacanths Subclass Dipnoi lungfish sister group to the tetrapods indicates extinct taxonSome palaeontologists contend that because Conodonta are chordates they are primitive fish For a fuller treatment of this taxonomy see the vertebrate article The position of hagfish in the phylum Chordata is not settled Phylogenetic research in 1998 and 1999 supported the idea that the hagfish and the lampreys form a natural group the Cyclostomata that is a sister group of the Gnathostomata 17 18 The various fish groups account for more than half of vertebrate species As of 2006 19 there are almost 28 000 known extant species of which almost 27 000 are bony fish with 970 sharks rays and chimeras and about 108 hagfish and lampreys A third of these species fall within the nine largest families from largest to smallest these families are Cyprinidae Gobiidae Cichlidae Characidae Loricariidae Balitoridae Serranidae Labridae and Scorpaenidae About 64 families are monotypic containing only one species The final total of extant species may grow to exceed 32 500 20 Each year new species are discovered and scientifically described As of 2016 21 there are over 32 000 documented species of bony fish and over 1 100 species of cartilaginous fish Species are lost through extinction see biodiversity crisis Recent examples are the Chinese paddlefish or the smooth handfish Diversity Main article Diversity of fish Agnatha Pacific hagfish Chondrichthyes Horn shark Actinopterygii Brown trout Sarcopterygii Coelacanth A relative of the seahorses the leafy seadragon s appendages allow it to camouflage in the form of crypsis with the surrounding seaweed The psychedelic mandarin dragonet is one of only two fish species where the blue colouring has been shown to be due to blue pigment containing chromatophores in the skin 22 The term fish most precisely describes any non tetrapod craniate i e an animal with a skull and in most cases a backbone that has gills throughout life and whose limbs if any are in the shape of fins 23 Unlike groupings such as birds or mammals fish are not a single clade but a paraphyletic collection of taxa including hagfishes lampreys sharks and rays ray finned fish coelacanths and lungfish 24 25 Indeed lungfish and coelacanths are closer relatives of tetrapods such as mammals birds amphibians etc than of other fish such as ray finned fish or sharks so the last common ancestor of all fish is also an ancestor to tetrapods As paraphyletic groups are no longer recognised in modern systematic biology the use of the term fish as a biological group must be avoided Many types of aquatic animals commonly referred to as fish are not fish in the sense given above examples include shellfish cuttlefish starfish crayfish and jellyfish In earlier times even biologists did not make a distinction sixteenth century natural historians classified also seals whales amphibians crocodiles even hippopotamuses as well as a host of aquatic invertebrates as fish 26 However according to the definition above all mammals including cetaceans like whales and dolphins are not fish In some contexts especially in aquaculture the true fish are referred to as finfish or fin fish to distinguish them from these other animals A typical fish is ectothermic has a streamlined body for rapid swimming extracts oxygen from water using gills or uses an accessory breathing organ to breathe atmospheric oxygen has two sets of paired fins usually one or two rarely three dorsal fins an anal fin and a tail fin has jaws has skin that is usually covered with scales and lays eggs Each criterion has exceptions Tuna swordfish and some species of sharks show some warm blooded adaptations they can heat their bodies significantly above ambient water temperature 24 Streamlining and swimming performance varies from fish such as tuna salmon and jacks that can cover 10 20 body lengths per second to species such as eels and rays that swim no more than 0 5 body lengths per second 27 Many groups of freshwater fish extract oxygen from the air as well as from the water using a variety of different structures Lungfish have paired lungs similar to those of tetrapods gouramis have a structure called the labyrinth organ that performs a similar function while many catfish such as Corydoras extract oxygen via the intestine or stomach 28 Body shape and the arrangement of the fins is highly variable covering such seemingly un fishlike forms as seahorses pufferfish anglerfish and gulpers Similarly the surface of the skin may be naked as in moray eels or covered with scales of a variety of different types usually defined as placoid typical of sharks and rays cosmoid fossil lungfish and coelacanths ganoid various fossil fish but also living gars and bichirs cycloid and ctenoid these last two are found on most bony fish 29 There are even fish that live mostly on land or lay their eggs on land near water 30 Mudskippers feed and interact with one another on mudflats and go underwater to hide in their burrows 31 A single undescribed species of Phreatobius has been called a true land fish as this worm like catfish strictly lives among waterlogged leaf litter 32 33 Many species live in underground lakes underground rivers or aquifers and are popularly known as cavefish 34 Fish range in size from the huge 16 metre 52 ft whale shark to the tiny 8 millimetre 0 3 in stout infantfish Fish species diversity is roughly divided equally between marine oceanic and freshwater ecosystems Coral reefs in the Indo Pacific constitute the center of diversity for marine fishes whereas continental freshwater fishes are most diverse in large river basins of tropical rainforests especially the Amazon Congo and Mekong basins More than 5 600 fish species inhabit Neotropical freshwaters alone such that Neotropical fishes represent about 10 of all vertebrate species on the Earth Exceptionally rich sites in the Amazon basin such as Cantao State Park can contain more freshwater fish species than occur in all of Europe 35 The deepest living fish in the ocean so far found is the Mariana snailfish Pseudoliparis swirei which lives at deeps of 8 000 meters 26 200 feet along the Mariana Trench near Guam 36 The diversity of living fish finfish is unevenly distributed among the various groups with teleosts making up the bulk of living fishes 96 and over 50 of all vertebrate species 21 The following cladogram 37 shows the evolutionary relationships of all groups of living fishes with their respective diversity 21 and the four limbed vertebrates tetrapods Diversity of various groups of fish and other vertebrates through time Lungfish are the closest living relatives of tetrapods four limbed vertebrates The bowfin Amia calva is the sole survivor of the halecomorph clade Vertebrates Jawless fish 118 living species hagfish lampreys Jawed vertebrates Cartilaginous fishes gt 1 100 living species sharks rays chimaeras Bony fishes Lobe fin fish Rhipidistia Tetrapoda gt 30 000 living species amphibians mammals reptiles birds Dipnoi 6 living species lungfish Actinistia 2 living species coelacanths Ray fin fish Cladistia 14 living species bichirs reedfish Actinopteri Chondrostei 27 living species sturgeons paddlefish Neopterygii Holostei Ginglymodi 7 living species gars alligator gars Halecomorphi 1 living species bowfin Teleostei gt 32 000 living species Anatomy and physiologyFurther information Fish anatomy and Fish physiology Organs 1 Liver 2 Gas bladder 3 Roe 4 Pyloric caeca 5 Stomach 6 Intestine Respiration See also Aquatic respiration Gills Tuna gills inside the head The fish head is oriented snout downwards with the view looking towards the mouth Most fish exchange gases using gills on either side of the pharynx Gills consist of threadlike structures called filaments Each filament contains a capillary network that provides a large surface area for exchanging oxygen and carbon dioxide Fish exchange gases by pulling oxygen rich water through their mouths and pumping it over their gills In some fish capillary blood flows in the opposite direction to the water causing countercurrent exchange The gills push the oxygen poor water out through openings in the sides of the pharynx Some fish like sharks and lampreys possess multiple gill openings However bony fish have a single gill opening on each side This opening is hidden beneath a protective bony cover called an operculum Juvenile bichirs have external gills a very primitive feature that they share with larval amphibians Air breathing Fish from multiple groups can live out of the water for extended periods Amphibious fish such as the mudskipper can live and move about on land for up to several days dubious discuss or live in stagnant or otherwise oxygen depleted water Many such fish can breathe air via a variety of mechanisms The skin of anguillid eels may absorb oxygen directly The buccal cavity of the electric eel may breathe air Catfish of the families Loricariidae Callichthyidae and Scoloplacidae absorb air through their digestive tracts 38 Lungfish with the exception of the Australian lungfish and bichirs have paired lungs similar to those of tetrapods and must surface to gulp fresh air through the mouth and pass spent air out through the gills Gar and bowfin have a vascularized swim bladder that functions in the same way Loaches trahiras and many catfish breathe by passing air through the gut Mudskippers breathe by absorbing oxygen across the skin similar to frogs A number of fish have evolved so called accessory breathing organs that extract oxygen from the air Labyrinth fish such as gouramis and bettas have a labyrinth organ above the gills that performs this function A few other fish have structures resembling labyrinth organs in form and function most notably snakeheads pikeheads and the Clariidae catfish family Breathing air is primarily of use to fish that inhabit shallow seasonally variable waters where the water s oxygen concentration may seasonally decline Fish dependent solely on dissolved oxygen such as perch and cichlids quickly suffocate while air breathers survive for much longer in some cases in water that is little more than wet mud At the extreme some air breathing fish are able to survive in damp burrows for weeks without water entering a state of aestivation summertime hibernation until water returns Air breathing fish can be divided into obligate air breathers and facultative air breathers Obligate air breathers such as the African lungfish must breathe air periodically or they suffocate Facultative air breathers such as the catfish Hypostomus plecostomus only breathe air if they need to and will otherwise rely on their gills for oxygen Most air breathing fish are facultative air breathers that avoid the energetic cost of rising to the surface and the fitness cost of exposure to surface predators 38 Circulation Didactic model of a fish heart Fish have a closed loop circulatory system The heart pumps the blood in a single loop throughout the body In most fish the heart consists of four parts including two chambers and an entrance and exit 39 The first part is the sinus venosus a thin walled sac that collects blood from the fish s veins before allowing it to flow to the second part the atrium which is a large muscular chamber The atrium serves as a one way antechamber sends blood to the third part ventricle The ventricle is another thick walled muscular chamber and it pumps the blood first to the fourth part bulbus arteriosus a large tube and then out of the heart The bulbus arteriosus connects to the aorta through which blood flows to the gills for oxygenation Digestion Jaws allow fish to eat a wide variety of food including plants and other organisms Fish ingest food through the mouth and break it down in the esophagus In the stomach food is further digested and in many fish processed in finger shaped pouches called pyloric caeca which secrete digestive enzymes and absorb nutrients Organs such as the liver and pancreas add enzymes and various chemicals as the food moves through the digestive tract The intestine completes the process of digestion and nutrient absorption Excretion As with many aquatic animals most fish release their nitrogenous wastes as ammonia Some of the wastes diffuse through the gills Blood wastes are filtered by the kidneys Saltwater fish tend to lose water because of osmosis Their kidneys return water to the body The reverse happens in freshwater fish they tend to gain water osmotically Their kidneys produce dilute urine for excretion Some fish have specially adapted kidneys that vary in function allowing them to move from freshwater to saltwater Scales Main article Fish scale The scales of fish originate from the mesoderm skin they may be similar in structure to teeth Sensory and nervous system Dorsal view of the brain of the rainbow trout Central nervous system Fish typically have quite small brains relative to body size compared with other vertebrates typically one fifteenth the brain mass of a similarly sized bird or mammal 40 However some fish have relatively large brains most notably mormyrids and sharks which have brains about as massive relative to body weight as birds and marsupials 41 Fish brains are divided into several regions At the front are the olfactory lobes a pair of structures that receive and process signals from the nostrils via the two olfactory nerves 40 The olfactory lobes are very large in fish that hunt primarily by smell such as hagfish sharks and catfish Behind the olfactory lobes is the two lobed telencephalon the structural equivalent to the cerebrum in higher vertebrates In fish the telencephalon is concerned mostly with olfaction 40 Together these structures form the forebrain Connecting the forebrain to the midbrain is the diencephalon in the diagram this structure is below the optic lobes and consequently not visible The diencephalon performs functions associated with hormones and homeostasis 40 The pineal body lies just above the diencephalon This structure detects light maintains circadian rhythms and controls color changes 40 The midbrain or mesencephalon contains the two optic lobes These are very large in species that hunt by sight such as rainbow trout and cichlids 40 The hindbrain or metencephalon is particularly involved in swimming and balance 40 The cerebellum is a single lobed structure that is typically the biggest part of the brain 40 Hagfish and lampreys have relatively small cerebellae while the mormyrid cerebellum is massive and apparently involved in their electrical sense 40 The brain stem or myelencephalon is the brain s posterior 40 As well as controlling some muscles and body organs in bony fish at least the brain stem governs respiration and osmoregulation 40 Sense organs Main article Sensory systems in fish Most fish possess highly developed sense organs Nearly all daylight fish have color vision that is at least as good as a human s see vision in fishes Many fish also have chemoreceptors that are responsible for extraordinary senses of taste and smell Although they have ears many fish may not hear very well Most fish have sensitive receptors that form the lateral line system which detects gentle currents and vibrations and senses the motion of nearby fish and prey 42 The sense information obtained from the lateral line system can be considered both a sense of touch and hearing Blind cave fish navigate almost entirely through the sensations from their lateral line system 43 Some fish such as catfish and sharks have the ampullae of Lorenzini electroreceptors that detect weak electric currents on the order of millivolt 44 Other fish like the South American electric fishes Gymnotiformes can produce weak electric currents which they use in navigation and social communication Fish orient themselves using landmarks and may use mental maps based on multiple landmarks or symbols Fish behavior in mazes reveals that they possess spatial memory and visual discrimination 45 Vision Main article Vision in fishes Vision is an important sensory system for most species of fish Fish eyes are similar to those of terrestrial vertebrates like birds and mammals but have a more spherical lens Their retinas generally 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 light Amongst jawless fish the lamprey has well developed eyes while the hagfish has only primitive eyespots 46 Fish vision shows adaptation to their visual environment for example deep sea fishes have eyes suited to the dark environment Hearing See also Hearing in fish Hearing is an important sensory system for most species of fish Fish sense sound using their lateral lines and their ears Cognition Further information Fish intelligence New research has expanded preconceptions about the cognitive capacities of fish For example manta rays have exhibited behavior linked to self awareness in mirror test cases Placed in front of a mirror individual rays engaged in contingency testing that is repetitive behavior aiming to check whether their reflection s behavior mimics their body movement 47 Wrasses have also passed the mirror test in a 2018 scientific study 48 49 Cases of tool use have also been noticed notably in the Choerodon family in archerfish and Atlantic cod 50 Capacity for pain Further information Pain in fish Experiments done by William Tavolga provide evidence that fish have pain and fear responses For instance in Tavolga s experiments toadfish grunted when electrically shocked and over time they came to grunt at the mere sight of an electrode 51 In 2003 Scottish scientists at the University of Edinburgh and the Roslin Institute concluded that rainbow trout exhibit behaviors often associated with pain in other animals Bee venom and acetic acid injected into the lips resulted in fish rocking their bodies and rubbing their lips along the sides and floors of their tanks which the researchers concluded were attempts to relieve pain similar to what mammals would do 52 53 Neurons fired in a pattern resembling human neuronal patterns 53 Professor James D Rose of the University of Wyoming claimed the study was flawed since it did not provide proof that fish possess conscious awareness particularly a kind of awareness that is meaningfully like ours 54 Rose argues that since fish brains are so different from human brains fish are probably not conscious in the manner humans are so that reactions similar to human reactions to pain instead have other causes Rose had published a study a year earlier arguing that fish cannot feel pain because their brains lack a neocortex 55 However animal behaviorist Temple Grandin argues that fish could still have consciousness without a neocortex because different species can use different brain structures and systems to handle the same functions 53 Animal welfare advocates raise concerns about the possible suffering of fish caused by angling Some countries such as Germany have banned specific types of fishing and the British RSPCA now formally prosecutes individuals who are cruel to fish 56 Emotion In 2019 scientists have shown that members of the monogamous species Amatitlania siquia exhibit pessimistic behavior when they are prevented from being with their partner 57 Muscular system Main article Fish locomotion The anatomy of Lampanyctodes hectoris 1 operculum gill cover 2 lateral line 3 dorsal fin 4 fat fin 5 caudal peduncle 6 caudal fin 7 anal fin 8 photophores 9 pelvic fins paired 10 pectoral fins paired Swim bladder of a rudd Scardinius erythrophthalmus Most fish move by alternately contracting paired sets of muscles on either side of the backbone These contractions form S shaped curves that move down the body As each curve reaches the back fin backward force is applied to the water and in conjunction with the fins moves the fish forward The fish s fins function like an airplane s flaps Fins also increase the tail s surface area increasing speed The streamlined body of the fish decreases the amount of friction from the water Since body tissue is denser than water fish must compensate for the difference or they will sink Many bony fish have an internal organ called a swim bladder that adjusts their buoyancy through manipulation of gases Endothermy Although most fish are exclusively ectothermic there are exceptions The only known bony fishes infraclass Teleostei that exhibit endothermy are in the suborder Scombroidei which includes the billfishes tunas and the butterfly kingfish a basal species of mackerel 58 and also the opah The opah a lampriform was demonstrated in 2015 to use whole body endothermy generating heat with its swimming muscles to warm its body while countercurrent exchange as in respiration minimizes heat loss 59 It is able to actively hunt prey such as squid and swim for long distances due to the ability to warm its entire body including its heart 60 which is a trait typically found in only mammals and birds in the form of homeothermy In the cartilaginous fishes class Chondrichthyes sharks of the families Lamnidae porbeagle mackerel salmon and great white sharks and Alopiidae thresher sharks exhibit endothermy The degree of endothermy varies from the billfishes which warm only their eyes and brain to the bluefin tuna and the porbeagle shark which maintain body temperatures in excess of 20 C 68 F above ambient water temperatures 58 Endothermy though metabolically costly is thought to provide advantages such as increased muscle strength higher rates of central nervous system processing and higher rates of digestion Reproductive system Further information Fish reproduction and Spawn biology Ovary of fish Corumbata Fish reproductive organs include testicles and ovaries In most species gonads are paired organs of similar size which can be partially or totally fused 61 There may also be a range of secondary organs that increase reproductive fitness In terms of spermatogonia distribution the structure of teleosts testes has two types in the most common spermatogonia occur all along the seminiferous tubules while in atherinomorph fish they are confined to the distal portion of these structures Fish can present cystic or semi cystic spermatogenesis in relation to the release phase of germ cells in cysts to the seminiferous tubules lumen 61 Fish ovaries may be of three types gymnovarian secondary gymnovarian or cystovarian In the first type the oocytes are released directly into the coelomic cavity and then enter the ostium then through the oviduct and are eliminated Secondary gymnovarian ovaries shed ova into the coelom from which they go directly into the oviduct In the third type the oocytes are conveyed to the exterior through the oviduct 62 Gymnovaries are the primitive condition found in lungfish sturgeon and bowfin Cystovaries characterize most teleosts where the ovary lumen has continuity with the oviduct 61 Secondary gymnovaries are found in salmonids and a few other teleosts Oogonia development in teleosts fish varies according to the group and the determination of oogenesis dynamics allows the understanding of maturation and fertilization processes Changes in the nucleus ooplasm and the surrounding layers characterize the oocyte maturation process 61 Postovulatory follicles are structures formed after oocyte release they do not have endocrine function present a wide irregular lumen and are rapidly reabsorbed in a process involving the apoptosis of follicular cells A degenerative process called follicular atresia reabsorbs vitellogenic oocytes not spawned This process can also occur but less frequently in oocytes in other development stages 61 Some fish like the California sheephead are hermaphrodites having both testes and ovaries either at different phases in their life cycle or as in hamlets have them simultaneously Over 97 of all known fish are oviparous 63 that is the eggs develop outside the mother s body Examples of oviparous fish include salmon goldfish cichlids tuna and eels In the majority of these species fertilisation takes place outside the mother s body with the male and female fish shedding their gametes into the surrounding water However a few oviparous fish practice internal fertilization with the male using some sort of intromittent organ to deliver sperm into the genital opening of the female most notably the oviparous sharks such as the horn shark and oviparous rays such as skates In these cases the male is equipped with a pair of modified pelvic fins known as claspers Marine fish can produce high numbers of eggs which are often released into the open water column The eggs have an average diameter of 1 millimetre 0 04 in Egg of lamprey Egg of catshark mermaids purse Egg of bullhead shark Egg of chimaeraThe newly hatched young of oviparous fish are called larvae They are usually poorly formed carry a large yolk sac for nourishment and are very different in appearance from juvenile and adult specimens The larval period in oviparous fish is relatively short usually only several weeks and larvae rapidly grow and change appearance and structure a process termed metamorphosis to become juveniles During this transition larvae must switch from their yolk sac to feeding on zooplankton prey a process which depends on typically inadequate zooplankton density starving many larvae In ovoviviparous fish the eggs develop inside the mother s body after internal fertilization but receive little or no nourishment directly from the mother depending instead on the yolk Each embryo develops in its own egg Familiar examples of ovoviviparous fish include guppies angel sharks and coelacanths Some species of fish are viviparous In such species the mother retains the eggs and nourishes the embryos Typically viviparous fish have a structure analogous to the placenta seen in mammals connecting the mother s blood supply with that of the embryo Examples of viviparous fish include the surf perches splitfins and lemon shark Some viviparous fish exhibit oophagy in which the developing embryos eat other eggs produced by the mother This has been observed primarily among sharks such as the shortfin mako and porbeagle but is known for a few bony fish as well such as the halfbeak Nomorhamphus ebrardtii 64 Intrauterine cannibalism is an even more unusual mode of vivipary in which the largest embryos eat weaker and smaller siblings This behavior is also most commonly found among sharks such as the grey nurse shark but has also been reported for Nomorhamphus ebrardtii 64 Aquarists commonly refer to ovoviviparous and viviparous fish as livebearers Acoustic communicationSee also Acoustic communication in aquatic animals Acoustic communication in fish involves the transmission of acoustic signals from one individual of a species to another The production of sounds as a means of communication among fish is most often used in the context of feeding aggression or courtship behaviour 3 The sounds emitted can vary depending on the species and stimulus involved Fish can produce either stridulatory sounds by moving components of the skeletal system or can produce non stridulatory sounds by manipulating specialized organs such as the swimbladder 65 Stridulatory French grunts Haemulon flavolineatum There are some species of fish that can produce sounds by rubbing or grinding their bones together These noises produced by bone on bone interactions are known as stridulatory sounds 65 An example of this is seen in Haemulon flavolineatum a species commonly referred to as the French grunt fish as it produces a grunting noise by grinding its teeth together 65 This behaviour is most pronounced when the H flavolineatum is in distress situations 65 The grunts produced by this species of fishes generate a frequency of approximately 700 Hz and last approximately 47 milliseconds 65 The H flavolineatum does not emit sounds with frequencies greater than 1000 Hz and does not detect sounds that have frequencies greater than 1050 Hz 65 In a study conducted by Oliveira et al 2014 the longsnout seahorse Hippocampus reidi was recorded producing two different categories of sounds clicks and growls The sounds emitted by the H reidi are accomplished by rubbing their coronet bone across the grooved section of their neurocranium 66 Clicking sounds were found to be primarily produced during courtship and feeding and the frequencies of clicks were within the range of 50 Hz 800 Hz 67 The frequencies were noted to be on the higher end of the range during spawning periods when the female and male fishes were less than fifteen centimeters apart 67 Growl sounds were produced when the H reidi encountered stressful situations such as handling by researchers 67 The growl sounds consist of a series of sound pulses and are emitted simultaneously with body vibrations 67 Non stridulatory Oyster toadfish Some fish species create noise by engaging specialized muscles that contract and cause swimbladder vibrations Oyster toadfish produce loud grunting sounds by contracting muscles located along the sides of their swim bladder known as sonic muscles 68 Female and male toadfishes emit short duration grunts often as a fright response 69 In addition to short duration grunts male toadfishes produce boat whistle calls 70 These calls are longer in duration lower in frequency and are primarily used to attract mates 70 The sounds emitted by the O tao have frequency range of 140 Hz to 260 Hz 70 The frequencies of the calls depend on the rate at which the sonic muscles contract 71 68 The red drum Sciaenops ocellatus produces drumming sounds by vibrating its swimbladder 72 Vibrations are caused by the rapid contraction of sonic muscles that surround the dorsal aspect of the swimbladder 72 These vibrations result in repeated sounds with frequencies that range from 100 to gt 200 Hz 72 The S ocellatus can produce different calls depending on the stimuli involved 72 The sounds created in courtship situations are different from those made during distressing events such as predatorial attacks 72 Unlike the males of the S ocellatus species the females of this species do not produce sounds and lack sound producing sonic muscles 72 DiseasesMain article Fish diseases and parasites Like other animals fish suffer from diseases and parasites To prevent disease they have a variety of defenses Non specific defenses include the skin and scales as well as the mucus layer secreted by the epidermis that traps and inhibits the growth of microorganisms If pathogens breach these defenses fish can develop an inflammatory response that increases blood flow to the infected region and delivers white blood cells that attempt to destroy pathogens Specific defenses respond to particular pathogens recognised by the fish s body i e an immune response 73 In recent years vaccines have become widely used in aquaculture and also with ornamental fish for example furunculosis vaccines in farmed salmon and koi herpes virus in koi 74 75 Some species use cleaner fish to remove external parasites The best known of these are the bluestreak cleaner wrasses of the genus Labroides found on coral reefs in the Indian and Pacific oceans These small fish maintain so called cleaning stations where other fish congregate and perform specific movements to attract the attention of the cleaners 76 Cleaning behaviors have been observed in a number of fish groups including an interesting case between two cichlids of the same genus Etroplus maculatus the cleaner and the much larger Etroplus suratensis 77 Immune system Immune organs vary by type of fish 78 In the jawless fish lampreys and hagfish true lymphoid organs are absent These fish rely on regions of lymphoid tissue within other organs to produce immune cells For example erythrocytes macrophages and plasma cells are produced in the anterior kidney or pronephros and some areas of the gut where granulocytes mature They resemble primitive bone marrow in hagfish Cartilaginous fish sharks and rays have a more advanced immune system They have three specialized organs that are unique to Chondrichthyes the epigonal organs lymphoid tissue similar to mammalian bone that surround the gonads the Leydig s organ within the walls of their esophagus and a spiral valve in their intestine These organs house typical immune cells granulocytes lymphocytes and plasma cells They also possess an identifiable thymus and a well developed spleen their most important immune organ where various lymphocytes 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 meninges membranes surrounding the central nervous system Their heart is frequently covered with tissue that contains lymphocytes reticular cells and a small number of macrophages The chondrostean kidney is an important hemopoietic organ where erythrocytes granulocytes lymphocytes and macrophages develop Like chondrostean fish the major immune tissues of bony fish or teleostei include the kidney especially the anterior kidney which houses many different immune cells 79 In addition teleost fish possess a thymus spleen and scattered immune areas within mucosal tissues e g in the skin gills gut and gonads Much like the mammalian immune system teleost erythrocytes neutrophils and granulocytes are believed to reside in the spleen whereas lymphocytes are the major cell type found in the thymus 80 81 In 2006 a lymphatic system similar to that in mammals was described in one species of teleost fish the zebrafish Although not confirmed as yet this system presumably will be where naive unstimulated T cells accumulate while waiting to encounter an antigen 82 B and T lymphocytes bearing immunoglobulins and T cell receptors respectively are found in all jawed fishes Indeed the adaptive immune system as a whole evolved in an ancestor of all jawed vertebrates 83 ConservationThe 2006 IUCN Red List names 1 173 fish species that are threatened with extinction 84 Included are species such as Atlantic cod 85 Devil s Hole pupfish 86 coelacanths 87 and great white sharks 88 Because fish live underwater they are more difficult to study than terrestrial animals and plants and information about fish populations is often lacking However freshwater fish seem particularly threatened because they often live in relatively small water bodies For example the Devil s Hole pupfish occupies only a single 3 by 6 metres 10 by 20 ft pool 89 Overfishing Whale sharks the largest species of fish are classified as endangered Main article Overfishing Overfishing is a major threat to edible fish such as cod and tuna 90 91 Overfishing eventually causes population known as stock collapse because the survivors cannot produce enough young to replace those removed Such commercial extinction does not mean that the species is extinct merely that it can no longer sustain a fishery One well studied example of fishery collapse is the Pacific sardine Sadinops sagax caerulues fishery off the California coast From a 1937 peak of 790 000 long tons 800 000 t the catch steadily declined to only 24 000 long tons 24 000 t in 1968 after which the fishery was no longer economically viable 92 The main tension between fisheries science and the fishing industry is that the two groups have different views on the resiliency of fisheries to intensive fishing In places such as Scotland Newfoundland and Alaska the fishing industry is a major employer so governments are predisposed to support it 93 94 On the other hand scientists and conservationists push for stringent protection warning that many stocks could be wiped out within fifty years 95 96 Habitat destruction See also Environmental impact of fishing A key stress on both freshwater and marine ecosystems is habitat degradation including water pollution the building of dams removal of water for use by humans and the introduction of exotic species 97 An example of a fish that has become endangered because of habitat change is the pallid sturgeon a North American freshwater fish that lives in rivers damaged by human activity 98 Exotic species Introduction of non native species occurs in many habitats A notable case in point is the Mediterranean Sea which has become a major hotspot of exotic invaders since the opening of the Suez Canal in 1869 Since that time a thousand marine species of all sorts fishes seaweeds invertebrates originating from the Red Sea and more broadly from the Indo Pacific have crossed the Canal from south to north to settle in the eastern Mediterranean Basin Nowadays many of these tropical migrants also called Lessepsian species have extended their range towards the west obviously favoured by the general warming of the Mediterranean The resulting change in biodiversity is without precedent in human memory and is accelerating a long term cross Basin survey engaged by the Mediterranean Science Commission recently documented 99 that in just twenty years from 2001 till 2021 no less than 107 alien fish species have reached the Mediterranean from both the tropical Atlantic and the Red Sea which is more than the total recorded during the whole 130 preceding years Another mode of introduction for marine species is transport across thousands of kms on ship hulls or in ballast waters Examples abound of marine organisms being transported in ballast water among them the invasive comb jelly Mnemiopsis leidyi the dangerous bacterium Vibrio cholerae or the fouling zebra mussel The Mediterranean and Black Seas with their high volume shipping from exotic harbors are particularly impacted by this problem 100 Deliberate introductions of species with market potential are another frequent vector one of the best studied examples is the introduction of the Nile perch into Lake Victoria in the 1960s Nile perch gradually exterminated the lake s 500 endemic cichlid species Some of them now survive in captive breeding programmes but others are probably extinct 101 Carp snakeheads 102 tilapia European perch brown trout rainbow trout and sea lampreys are other examples of fish that have caused problems by being introduced into alien environments Importance to humansEconomic Main articles Commercial fishing Fishing industry Aquaculture and Fish farming These fish farming ponds were created as a cooperative project in a rural village Fish counter display at the Oulu Market Hall in Oulu Finland Throughout history humans have used fish as a food source for dietary protein Historically and today most fish harvested for human consumption has come by means of catching wild fish However fish farming which has been practiced since about 3 500 BCE in ancient China 103 is becoming increasingly important in many nations Overall about one sixth of the world s protein is estimated to be provided by fish 104 That proportion is considerably elevated in some developing nations and regions heavily dependent on seafood In a similar manner fish have been tied to primary industry and associated food feed pharmaceutical production and service industries Catching fish for the purpose of food or sport is known as fishing while the organized effort by humans to catch fish is called a fishery which also describes the area where such enterprise operates Fisheries are a huge global business and provide income for millions of people 104 The annual yield from all fisheries worldwide is about 154 million tons 105 with popular species including herring cod anchovy tuna flounder and salmon However the term fishery is broadly applied and includes more organisms than just fish such as mollusks and crustaceans which are often collectively called shellfish when used as food Recreation A Bengali fish vendor from Sylhet Fishkeeping Main article Fishkeeping Fish have been recognized as a source of beauty for almost as long as used for food appearing in cave art being raised as ornamental fish in ponds and displayed in aquariums in homes offices or public settings Recreational fishing Main articles Recreational fishing Angling and Fishing tournament Recreational fishing is fishing primarily for pleasure or competition it can be contrasted with commercial fishing which is fishing for profit or artisanal fishing which is fishing primarily for food The most common form of recreational fishing is done with a rod reel line hooks and any one of a wide range of baits Recreational fishing is particularly popular in North America and Europe and state provincial and federal government agencies actively management target fish species 106 107 Angling is a method of fishing specifically the practice of catching fish by means of an angle hook Anglers must select the right hook cast accurately and retrieve at the right speed while considering water and weather conditions species fish response time of the day and other factors Culture Main article Fish in culture Avatar of Vishnu as a Matsya Fish themes have symbolic significance in many religions In ancient Mesopotamia fish offerings were made to the gods from the very earliest times 108 Fish were also a major symbol of Enki the god of water 108 Fish frequently appear as filling motifs in cylinder seals from the Old Babylonian c 1830 BC c 1531 BC and Neo Assyrian 911 609 BC periods 108 Starting during the Kassite Period c 1600 BC c 1155 BC and lasting until the early Persian Period 550 30 BC healers and exorcists dressed in ritual garb resembling the bodies of fish 108 During the Seleucid Period 312 63 BC the legendary Babylonian culture hero Oannes described by Berossus was said to have dressed in the skin of a fish 108 Fish were sacred to the Syrian goddess Atargatis 109 and during her festivals only her priests were permitted to eat them 109 The ichthus is a Christian symbol of a fish signifying that the person who uses it is a Christian 109 110 In the Book of Jonah a work of Jewish literature probably written in the fourth century BC the central figure a prophet named Jonah is swallowed by a giant fish after being thrown overboard by the crew of the ship he is travelling on 111 112 113 The fish later vomits Jonah out on shore after three days 111 112 113 This book was later included as part of the Hebrew Bible or Christian Old Testament 114 115 and a version of the story it contains is summarized in Surah 37 139 148 of the Quran 116 Early Christians used the ichthys a symbol of a fish to represent Jesus 109 110 because the Greek word for fish IX8YS Ichthys could be used as an acronym for Ihsoῦs Xristos 8eoῦ Yἱos Swthr Iesous Christos Theou Huios Soter meaning Jesus Christ Son of God Saviour 109 110 The gospels also refer to fishers of men 117 and feeding the multitude In the dhamma of Buddhism the fish symbolize happiness as they have complete freedom of movement in the water Among the deities said to take the form of a fish are Ika Roa of the Polynesians Dagon of various ancient Semitic peoples the shark gods of Hawaiʻi and Matsya of the Hindus The astrological symbol Pisces is based on a constellation of the same name but there is also a second fish constellation in the night sky Piscis Austrinus 118 Fish feature prominently in art and literature in movies such as Finding Nemo and books such as The Old Man and the Sea Large fish particularly sharks have frequently been the subject of horror movies and thrillers most notably the novel Jaws which spawned a series of films of the same name that in turn inspired similar films or parodies such as Shark Tale and Snakehead Terror Piranhas are shown in a similar light to sharks in films such as Piranha however contrary to popular belief the red bellied piranha is actually a generally timid scavenger species that is unlikely to harm humans 119 Legends of half human half fish mermaids have featured in folklore including the stories of Hans Christian Andersen Terminology Fish or fishes Though often used interchangeably in biology these words have different meanings Fish is used as a singular noun or as a plural to describe multiple individuals from a single species Fishes is used to describe different species or species groups 120 121 122 Thus a pond would be said to contain 120 fish if all were from a single species or 120 fishes if these included a mix of several species The distinction is similar to that between people and peoples True fish or finfish In biology the term fish is most strictly used to describe any animal with a backbone gills throughout life and limbs if any in the shape of fins 23 Many types of aquatic animals with common names ending in fish are not fish in this sense examples include shellfish cuttlefish starfish crayfish and jellyfish In earlier times even biologists did not make a distinction sixteenth century natural historians classified also seals whales amphibians crocodiles even hippopotamuses as well as a host of aquatic invertebrates as fish 26 In fisheries the term fish is used as a collective term and includes mollusks crustaceans and any aquatic animal which is harvested 123 The strict biological definition of a fish above is sometimes called a true fish True fish are also referred to as finfish or fin fish to distinguish them from other aquatic life harvested in fisheries or aquaculture Shoal or school Main article Shoaling and schooling These goldband fusiliers are schooling because their swimming is synchronised An assemblage of fish merely using some localised resource such as food or nesting sites is known simply as an aggregation When fish come together in an interactive social grouping then they may be forming either a shoal or a school depending on the degree of organisation A shoal is a loosely organised group where each fish swims and forages independently but is attracted to other members of the group and adjusts its behaviour such as swimming speed so that it remains close to the other members of the group Schools of fish are much more tightly organised synchronising their swimming so that all fish move at the same speed and in the same direction Shoaling and schooling behaviour is believed to provide a variety of advantages 124 Examples Cichlids congregating at lekking sites form an aggregation Many minnows and characins form shoals Anchovies herrings and silversides are classic examples of schooling fish The most common collective nouns for a group of fish in general are school and shoal Both the words have evolved from the same common Dutch root schole meaning a troop or crowd While the words school and shoal have different meanings within biology the distinctions are often ignored by non specialists who treat the words as synonyms Thus speakers of British English commonly use shoal to describe any grouping of fish and speakers of American English commonly use school just as loosely 125 See also Fish portalMain article Outline of fish For a topical guide to sharks see Outline of sharks Angling sport fishing Aquaculture Aquarium Catch and release Deep sea fish Fish acute toxicity syndrome Fish anatomy Fish as food Fish development Fishing fishing for food Fishkeeping Forage fish Ichthyology List of fish common names List of fish families Marine biology Marine vertebrates Mercury in fish Otolith Bone used for determining the age of a fish Pregnancy fish Seafood Shoaling and schooling Walking fishNotes Goldman K J 1997 Regulation of body temperature in the white shark Carcharodon carcharias Journal of Comparative Physiology B Biochemical Systemic and Environmental Physiology 167 6 423 429 doi 10 1007 s003600050092 S2CID 28082417 Archived from the original on 6 April 2012 Retrieved 12 October 2011 Carey F G Lawson K D February 1973 Temperature regulation in free swimming bluefin tuna Comparative Biochemistry and Physiology A 44 2 375 392 doi 10 1016 0300 9629 73 90490 8 PMID 4145757 a b Weinmann S R Black A N Richter M L Itzkowitz M Burger R M February 2017 Territorial vocalization in sympatric damselfish acoustic characteristics and intruder discrimination Bioacoustics 27 1 87 102 doi 10 1080 09524622 2017 1286263 S2CID 89625932 Yancey PH Gerringer ME Drazen JC Rowden AA Jamieson A 2014 Marine fish may be biochemically constrained from inhabiting the deepest ocean depths Proc Natl Acad Sci U S A 111 12 4461 4465 Bibcode 2014PNAS 111 4461Y doi 10 1073 pnas 1322003111 PMC 3970477 PMID 24591588 FishBase Search FishBase March 2020 Archived from the original on 3 March 2020 Retrieved 19 March 2020 Zoology PDF Greene Harry W 1 January 1998 We are primates and we are fish Teaching monophyletic organismal biology Integrative Biology Issues News and Reviews 1 3 108 111 doi 10 1002 sici 1520 6602 1998 1 3 lt 108 aid inbi5 gt 3 0 co 2 t ISSN 1520 6602 DWDS Digitales Worterbuch der deutschen Sprache DWDS in German Retrieved 21 January 2023 Winfred Philipp Lehmann Helen Jo J Hewitt Sigmund Feist A Gothic etymological dictionary 1986 s v fisks p 118 fish n 1 OED Online Oxford University Press retrieved 21 January 2023 Carl Darling Buck A Dictionary of Selected Synonyms in the Principal Indo European Languages 1949 s v section 3 65 p 184 Monster fish crushed opposition with strongest bite ever Smh com au 30 November 2006 Archived from the original on 2 April 2013 Retrieved 26 February 2013 Giles Sam Friedman Matt Brazeau Martin D 12 January 2015 Osteichthyan like cranial conditions in an Early Devonian stem gnathostome Nature 520 7545 82 85 Bibcode 2015Natur 520 82G doi 10 1038 nature14065 ISSN 1476 4687 PMC 5536226 PMID 25581798 Davis S Finarelli J Coates M 2012 Acanthodes and shark like conditions in the last common ancestor of modern gnathostomes Nature 486 7402 247 250 Bibcode 2012Natur 486 247D doi 10 1038 nature11080 PMID 22699617 S2CID 4304310 Romer A S amp T S Parsons 1977 The Vertebrate Body 5th ed Saunders Philadelphia 6th ed 1985 Benton M J 1998 The quality of the fossil record of vertebrates pp 269 303 in Donovan S K and Paul C R C eds The adequacy of the fossil record Fig 2 Wiley New York 312 pp Shigehiro Kuraku Daisuke Hoshiyama Kazutaka Katoh Hiroshi Suga Takashi Miyata 1999 Monophyly of Lampreys and Hagfishes Supported by Nuclear DNA Coded Genes J Mol Evol 1999 49 729 735 J Mallatt J Sullivan 1998 28S and 18S rDNA sequences support the monophyly of lampreys and hagfishes Molecular Biology and Evolution V 15 Issue 12 pp 1706 1718 Nelson 2006 pp 4 5 Nelson 2006 p 3 a b c Nelson Joseph S 2016 Fishes of the World John Wiley amp Sons Inc ISBN 978 1 118 34233 6 Goda M R Fujii 2009 Blue Chromatophores in Two Species of Callionymid Fish Zoological Science 12 6 811 813 doi 10 2108 zsj 12 811 S2CID 86385679 a b Nelson 2006 p 2 a b Helfman Collette amp Facey 1997 p 3 Tree of life web project Chordates Archived 24 February 2007 at the Wayback Machine a b Cleveland P Hickman Jr Larry S Roberts Allan L Larson 2001 Integrated Principles of Zoology McGraw Hill Publishing Co ISBN 978 0 07 290961 6 Helfman Collette amp Facey 1997 p 103 Helfman Collette amp Facey 1997 pp 53 57 Helfman Collette amp Facey 1997 pp 33 36 Martin K L M 2014 Beach Spawning Fishes Reproduction in an Endangered Ecosystem CRC Press ISBN 978 1 4822 0797 2 Froese Rainer Pauly Daniel eds 2006 Periophthalmus barbarus in FishBase November 2006 version Planet Catfish Cat eLog Heptapteridae Phreatobius Phreatobius sp 1 Planet Catfish Archived from the original on 23 October 2006 Retrieved 26 November 2006 Henderson P A Walker I 1990 Spatial organization and population density of the fish community of the litter banks within a central Amazonian blackwater stream Journal of Fish Biology 37 3 401 411 doi 10 1111 j 1095 8649 1990 tb05871 x Aldemaro R ed 2001 The Biology of Hypogean Fishes Developments in environmental biology of fishes Vol 21 ISBN 978 1 4020 0076 8 central3 to gov br https central3 to gov br arquivo 24 199 Retrieved 21 January 2023 a href Template Cite web html title Template Cite web cite web a Missing or empty title help There s a deeper fish in the sea UW News Retrieved 11 December 2020 Friedman Matt Sallan Lauren Cole June 2012 Five hundred million years of extinczion and recovery A Phanerozoic survey of large scale diversity patterns in fishes Palaeontology 55 4 707 742 doi 10 1111 j 1475 4983 2012 01165 x S2CID 59423401 a b Armbruster Jonathan W 1998 Modifications of the Digestive Tract for Holding Air in Loricariid and Scoloplacid Catfishes PDF Copeia 1998 3 663 675 doi 10 2307 1447796 JSTOR 1447796 Archived from the original PDF on 26 March 2009 Retrieved 25 June 2009 Setaro John F 1999 Circulatory System Microsoft Encarta 99 a b c d e f g h i j k Helfman Collette amp Facey 1997 pp 48 49 Helfman Collette amp Facey 1997 p 191 Orr James 1999 Fish Microsoft Encarta 99 ISBN 978 0 8114 2346 5 Godfrey Smith Peter 10 November 2020 Kingfish Metazoa New York Farrar Straus and Giroux ISBN 9780374207946 Albert J S and W G R Crampton 2005 Electroreception and electrogenesis pp 431 472 in The Physiology of Fishes 3rd Edition D H Evans and J B Claiborne eds CRC Press Sciences Journal of Undergraduate Life Appropriate maze methodology to study learning in fish PDF Archived from the original PDF on 6 July 2011 Retrieved 28 May 2009 Campbell Neil A Reece Jane B 2005 Biology Seventh ed San Francisco Benjamin Cummings Ari Csilla D Agostino Dominic P 1 May 2016 Contingency checking and self directed behaviors in giant manta rays Do elasmobranchs have self awareness Journal of Ethology 34 2 167 174 doi 10 1007 s10164 016 0462 z ISSN 1439 5444 S2CID 254134775 Kohda Masanori Hotta Takashi Takeyama Tomohiro Awata Satoshi Tanaka Hirokazu Asai Jun ya Jordan L Alex 21 August 2018 Cleaner wrasse pass the mark test What are the implications for consciousness and self awareness testing in animals 397067 doi 10 1101 397067 S2CID 91375693 a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help Scientists find some fish can recognise themselves in mirror the Guardian 7 February 2019 Retrieved 21 January 2023 Fishes Use Problem Solving and Invent Tools article at Scientific American Archived 18 May 2020 at the Wayback Machine Dunayer Joan Fish Sensitivity Beyond the Captor s Grasp The Animals Agenda July August 1991 pp 12 18 Kirby Alex 30 April 2003 Fish do feel pain scientists say BBC News Archived from the original on 15 February 2009 Retrieved 4 January 2010 a b c Grandin Temple Johnson Catherine 2005 Animals in Translation New York City Scribner pp 183 184 ISBN 978 0 7432 4769 6 Rose J D 2003 A Critique of the paper Do fish have nociceptors Evidence for the evolution of a vertebrate sensory system PDF Archived from the original PDF on 8 June 2011 Retrieved 21 May 2011 Rose James D 2002 Do Fish Feel Pain Archived from the original on 20 January 2013 Retrieved 27 September 2007 Leake Jonathan 14 March 2004 Anglers to face RSPCA checks The Sunday Times Laubu Chloe Louapre Philippe Dechaume Moncharmont Francois Xavier 2019 Pair bonding influences affective state in a monogamous fish species Proc R Soc B 286 1904 20190760 doi 10 1098 rspb 2019 0760 PMC 6571461 PMID 31185864 a b Block BA Finnerty JR 1993 Endothermy in fishes a phylogenetic analysis of constraints predispositions and selection pressures PDF Environmental Biology of Fishes 40 3 283 302 doi 10 1007 BF00002518 S2CID 28644501 Wegner Nicholas C Snodgrass Owyn E Dewar Heidi Hyde John R 15 May 2015 Whole body endothermy in a mesopelagic fish the opah Lampris guttatus Science 348 6236 786 789 Bibcode 2015Sci 348 786W doi 10 1126 science aaa8902 ISSN 0036 8075 PMID 25977549 S2CID 17412022 Warm Blood Makes Opah an Agile Predator Southwest Fisheries Science Center 12 May 2015 Archived from the original on 20 January 2018 Retrieved 7 March 2018 a b c d e Guimaraes Cruz Rodrigo J dos Santos Jose E Santos Gilmar B July September 2005 Gonadal structure and gametogenesis of Loricaria lentiginosa Isbrucker Pisces Teleostei Siluriformes Rev Bras Zool 22 3 556 564 doi 10 1590 S0101 81752005000300005 ISSN 0101 8175 Brito M F G Bazzoli N 2003 Reproduction of the surubim catfish Pisces Pimelodidae in the Sao Francisco River Pirapora Region Minas Gerais Brazil Arquivo Brasileiro de Medicina Veterinaria e Zootecnia 55 5 624 633 doi 10 1590 S0102 09352003000500018 ISSN 0102 0935 Peter Scott Livebearing Fishes p 13 Tetra Press 1997 ISBN 1 56465 193 2 a b Meisner A amp Burns J Viviparity in the Halfbeak Genera Dermogenys and Nomorhamphus Teleostei Hemiramphidae Journal of Morphology 234 pp 295 317 1997 a b c d e f Bertucci F Ruppe L Wassenbergh S V Compere P Parmentier E 29 October 2014 New Insights into the Role of the Pharyngeal Jaw Apparatus in the Sound Producing Mechanism of Haemulon Flavolineatum Haemulidae Journal of Experimental Biology 217 21 3862 3869 doi 10 1242 jeb 109025 PMID 25355850 Colson D J Patek S N Brainerd E L Lewis S M February 1998 Sound production during feeding in Hippocampus seahorses Syngnathidae Environmental Biology of Fishes 51 2 221 229 doi 10 1023 A 1007434714122 S2CID 207648816 a b c d Oliveira T P R Ladich F Abed Navandi D Souto A S Rosa I L 26 June 2014 Sounds produced by the longsnout seahorse a study of their structure and functions Journal of Zoology 294 2 114 121 doi 10 1111 jzo 12160 a b Fine L F King C B Cameron T M 16 October 2009 Acoustical properties of the swimbladder in the oyster toadfish Opsanus tau Journal of Experimental Biology 212 21 3542 3552 doi 10 1242 jeb 033423 PMC 2762879 PMID 19837896 Fine M L Waybright T D 15 October 2015 Grunt variation in the oyster toadfish Opsanus tau effect of size and sex PeerJ 3 1330 e1330 doi 10 7717 peerj 1330 PMC 4662586 PMID 26623178 a b c Ricci S W Bohnenstiehl D R Eggleston D B Kellogg M L Lyon R P 8 August 2017 Oyster toadfish Opsanus tau boatwhistle call detection and patterns within a large scale oyster restoration site PLOS ONE 12 8 e0182757 Bibcode 2017PLoSO 1282757R doi 10 1371 journal pone 0182757 PMC 5549733 PMID 28792543 Skoglund C R 1 August 1961 Functional analysis of swimbladder muscles engaged in sound productivity of the toadfish Journal of Cell Biology 10 4 187 200 doi 10 1083 jcb 10 4 187 PMC 2225107 PMID 19866593 a b c d e f Parmentier E Tock J Falguiere J C Beauchaud M 22 May 2014 Sound production in Sciaenops ocellatus Preliminary study for the development of acoustic cues in aquaculture PDF Aquaculture 432 204 211 doi 10 1016 j aquaculture 2014 05 017 Helfman Collette amp Facey 1997 pp 95 96 R C Cipriano G L Bullock 2001 Furunculosis And Other Diseases Caused By Aeromonas salmonicida PDF Report Fish Disease Leaflet 66 U S Department of the Interior Archived from the original PDF on 7 May 2009 Retrieved 3 July 2009 Hartman K H et al 2004 Koi Herpes Virus KHV Disease Fact Sheet VM 149 PDF University of Florida Institute of Food and Agricultural Sciences Archived PDF from the original on 6 February 2007 Helfman Collette amp Facey 1997 p 380 Wyman Richard L Ward Jack A 1972 A Cleaning Symbiosis between the Cichlid Fishes Etroplus maculatus and Etroplus suratensis I Description and Possible Evolution Copeia 1972 4 834 838 doi 10 2307 1442742 JSTOR 1442742 A G Zapata A Chiba and A Vara Cells and tissues of the immune system of fish In The Fish Immune System Organism Pathogen and Environment Fish Immunology Series eds G Iwama and T Nakanishi New York Academic Press 1996 pp 1 55 D P Anderson Fish Immunology S F Snieszko and H R Axelrod eds Hong Kong TFH Publications Inc Ltd 1977 Chilmonczyk S 1992 The thymus in fish development and possible function in the immune response Annual Review of Fish Diseases 2 181 200 doi 10 1016 0959 8030 92 90063 4 Hansen J D Zapata A G 1998 Lymphocyte development in fish and amphibians Immunological Reviews 166 199 220 doi 10 1111 j 1600 065x 1998 tb01264 x PMID 9914914 S2CID 7965762 Kuchler AM Gjini E Peterson Maduro J Cancilla B Wolburg H Schulte Merker S 2006 Development of the Zebrafish Lymphatic System Requires Vegfc Signaling PDF Current Biology 16 12 1244 1248 doi 10 1016 j cub 2006 05 026 PMID 16782017 Flajnik M F Kasahara M 2009 Origin and evolution of the adaptive immune system genetic events and selective pressures Nature Reviews Genetics 11 1 47 59 doi 10 1038 nrg2703 PMC 3805090 PMID 19997068 Table 1 Numbers of threatened species by major groups of organisms 1996 2004 iucnredlist org Archived from the original on 30 June 2006 Retrieved 18 January 2006 Sobel J 1996 Gadus morhua IUCN Red List of Threatened Species 1996 e T8784A12931575 doi 10 2305 IUCN UK 1996 RLTS T8784A12931575 en Retrieved 11 November 2021 NatureServe 2014 Cyprinodon diabolis IUCN Red List of Threatened Species 2014 e T6149A15362335 doi 10 2305 IUCN UK 2014 3 RLTS T6149A15362335 en Retrieved 11 November 2021 Musick J A 2000 Latimeria chalumnae IUCN Red List of Threatened Species 2000 e T11375A3274618 doi 10 2305 IUCN UK 2000 RLTS T11375A3274618 en Retrieved 11 November 2021 Rigby C L Barreto R Carlson J Fernando D Fordham S Francis M P Herman K Jabado R W Liu K M Lowe C G Marshall A Pacoureau N Romanov E Sherley R B Winker H 2019 Carcharodon carcharias IUCN Red List of Threatened Species 2019 e T3855A2878674 Retrieved 19 December 2019 Helfman Collette amp Facey 1997 pp 449 450 Call to halt cod over fishing BBC News 5 January 2007 Archived from the original on 17 January 2007 Retrieved 18 January 2006 Tuna groups tackle overfishing BBC News 26 January 2007 Archived from the original on 21 January 2009 Retrieved 18 January 2006 Helfman Collette amp Facey 1997 p 462 UK must shield fishing industry BBC News 3 November 2006 Archived from the original on 30 November 2006 Retrieved 18 January 2006 EU fish quota deal hammered out BBC News 21 December 2006 Archived from the original on 26 December 2006 Retrieved 18 January 2006 Ocean study predicts the collapse of all seafood fisheries by 2050 phys org Archived from the original on 15 March 2007 Retrieved 13 January 2006 Atlantic bluefin tuna could soon be commercially extinct Archived from the original on 30 April 2007 Retrieved 18 January 2006 Helfman Collette amp Facey 1997 p 463 Threatened and Endangered Species Pallid Sturgeon Scaphirhynchus Fact Sheet Archived from the original on 26 November 2005 Retrieved 18 March 2016 CIESM Online book store ciesm org Retrieved 21 January 2023 Briand Frederic and Galil Bella 2002 Alien marine organisms introduced by ships An overview https www researchgate net publication 240305530 Spinney Laura 4 August 2005 The little fish fight back The Guardian London Retrieved 18 January 2006 Stop That Fish The Washington Post 3 July 2002 Archived from the original on 3 November 2012 Retrieved 26 August 2007 Spalding Mark 11 July 2013 Sustainable Ancient Aquaculture National Geographic Archived from the original on 18 May 2015 Retrieved 13 August 2015 a b Helfman Gene S 2007 Fish Conservation A Guide to Understanding and Restoring Global Aquatic Biodiversity and Fishery Resources Island Press p 11 ISBN 978 1 59726 760 1 World Review of Fisheries and Aquaculture PDF fao org Food and Agriculture Organization of the United Nations Archived PDF from the original on 28 August 2015 Retrieved 13 August 2015 Beard T Douglas ed 2011 The Angler in the Environment Social Economic Biological and Ethical Dimensions Bethesda MD American Fisheries Society p 365 ISBN 978 1 934874 24 0 Hickley Phil Tompkins Helena eds 1998 Recreational Fisheries Social Economic and Management Aspects Wiley Blackwell p 328 ISBN 978 0 852 38248 6 a b c d e Black Jeremy Green Anthony 1992 Gods Demons and Symbols of Ancient Mesopotamia An Illustrated Dictionary The British Museum Press pp 82 83 ISBN 978 0 7141 1705 8 Archived from the original on 20 February 2018 a b c d e Hyde Walter Woodburn 2008 1946 Paganism to Christianity in the Roman Empire Eugene Oregon Wipf and Stock Publishers pp 57 58 ISBN 978 1 60608 349 9 a b c Coffman Elesha 8 August 2008 What is the origin of the Christian fish symbol Christianity Today Retrieved 13 August 2015 a b Sherwood Yvonne 2000 A Biblical Text and Its Afterlives The Survival of Jonah in Western Culture Cambridge England Cambridge University Press pp 1 8 ISBN 978 0 521 79561 6 a b Ziolkowski Jan M 2007 Fairy Tales from Before Fairy Tales The Medieval Latin Past of Wonderful Lies Ann Arbor Michigan University of Michigan Press p 80 ISBN 978 0 472 03379 9 a b Gaines Janet Howe 2003 Forgiveness in a Wounded World Jonah s Dilemma Atlanta Georgia Society of Biblical Literature pp 8 9 ISBN 978 1 58983 077 6 Band Arnold J 2003 Studies in Modern Jewish Literature JPS Scholar of Distinction Series Philadelphia Pennsylvania The Jewish Publication Society pp 106 107 ISBN 978 0 8276 0762 0 Person Raymond 1996 In Conversation with Jonah Conversation Analysis Literary Criticism and the Book of Jonah Sheffield England Sheffield Academic Press p 155 ISBN 978 1 85075 619 4 Vicchio Stephen J 2008 Biblical Figures in the Islamic Faith Eugene Oregon Wipf amp Stock p 67 ISBN 978 1 55635 304 8 Matthew 4 19 Piscis Austrinus allthesky com The Deep Photographic Guide to the Constellations Archived from the original on 25 November 2015 Retrieved 1 November 2015 Zollinger Sue Anne 3 July 2009 Piranha Ferocious Fighter or Scavenging Softie A Moment of Science Indiana Public Media Archived from the original on 17 October 2015 Retrieved 1 November 2015 Pauly Daniel 13 May 2004 Fish es Darwin s Fishes An Encyclopedia of Ichthyology Ecology and Evolution Cambridge University Press p 77 ISBN 978 1 139 45181 9 Archived from the original on 8 February 2016 Nelson Joseph S Paetz Martin Joseph 1992 The Fishes of Alberta PDF University of Alberta p 400 ISBN 978 0 88864 236 3 Archived from the original PDF on 7 April 2014 Helfman Collette amp Facey 1997 p 5 Fisheries FAO TERM PORTAL FAO Helfman Collette amp Facey 1997 p 375 Pitcher T J Parish J K 1993 Functions of shoaling behaviour in teleosts In Pitcher T J ed Behaviour of teleost fishes New York Chapman and Hall pp 363 440 ISBN 9780412429309 Archived from the original on 5 April 2017 ReferencesHelfman G Collette B Facey D 1997 The Diversity of Fishes 1st ed Wiley Blackwell ISBN 978 0 86542 256 8 Nelson Joseph S 2006 Fishes of the World PDF 4th ed John Wiley amp Sons ISBN 978 0 471 75644 6 Archived from the original PDF on 5 March 2013 Retrieved 30 April 2013 Further readingEschmeyer William N Fong Jon David 2013 Catalog of Fishes California Academy of Sciences Helfman G Collette B Facey D Bowen B 2009 The Diversity of Fishes Biology Evolution and Ecology 2nd ed Wiley Blackwell ISBN 978 1 4051 2494 2 Moyle Peter B 1993 Fish An Enthusiast s Guide University of California Press ISBN 978 0 520 91665 4 good lay text Moyle Peter B Cech Joseph J 2003 Fishes An Introduction to Ichthyology 5th ed Benjamin Cummings ISBN 978 0 13 100847 2 Scales Helen 2018 Eye of the shoal A Fishwatcher s Guide to Life the Ocean and Everything Bloomsbury Sigma ISBN 978 1 4729 3684 4 Shubin Neil 2009 Your inner fish A journey into the 3 5 billion year history of the human body Vintage Books ISBN 978 0 307 27745 9 UCTV interview Archived 14 January 2021 at the Wayback MachineExternal links Wikimedia Commons has media related to wbr Fish wbr Actinopterygii wbr Marine aquarium fish and wbr Freshwater aquarium fish Wikiquote has quotations related to Fish Look up fish in Wiktionary the free dictionary Wikispecies has information related to Actinopterygii Wikisource has the text of the 1911 Encyclopaedia Britannica article Fish ANGFA Illustrated database of freshwater fishes of Australia and New Guinea Fischinfos de Illustrated database of the freshwater fishes of Germany at the Wayback Machine archived 30 November 2011 in German FishBase online Comprehensive database with information on over 29 000 fish species Fisheries and Illinois Aquaculture Center Data outlet for fisheries and aquaculture research center in the central US at archive today archived 15 December 2012 Philippines Fishes Database with thousands of Philippine Fishes photographed in natural habitat The Native Fish Conservancy Conservation and study of North American freshwater fishes at the Wayback Machine archived 12 March 2008 United Nation Fisheries and Aquaculture Department Fish and seafood utilization University of Washington Libraries Digital Collections Digital collection of freshwater and marine fish images Davenport Charles B Ingersoll Ernest 1905 Fish New International Encyclopedia Retrieved from https en wikipedia org w index php title Fish amp oldid 1136178794, wikipedia, wiki, book, books, library,

article

, read, download, free, free download, mp3, video, mp4, 3gp, jpg, jpeg, gif, png, picture, music, song, movie, book, game, games.