query: what are the little fish that attach themselves to sharks

pos: Remora have been observed attaching to divers as well. They swim well on their own, with a sinuous, or curved, motion. Remora front dorsal fins have evolved to enable them to adhere by suction to smooth surfaces and they spend their lives clinging to a host animal such as a whale, turtle, shark or ray. It is probably a mutualistic arrangement as the remora can move around on the host, removing ectoparasites and loose flakes of skin, while benefiting from the protection provided by the host, and the constant flow of water across its gills. Although it was initially believed that

pos: Spearfish remora remora ("Remora remora"). Although more than one remora can attach to a single host, it is not clear how remoras come together to breed. Spearfish remora The spearfish remora ("Remora brachyptera") is a species of remora with a worldwide distribution in tropical and subtropical seas. Remoras attach themselves to other fish with a sucker on the head and this fish is almost exclusively found living on billfishes or swordfishes, and sometimes on sharks. This species can reach in total length, though most do not exceed . It is an elongated cylindrical fish, usually whitish or pale blue in life, but

pos: Spearfish remora Spearfish remora The spearfish remora ("Remora brachyptera") is a species of remora with a worldwide distribution in tropical and subtropical seas. Remoras attach themselves to other fish with a sucker on the head and this fish is almost exclusively found living on billfishes or swordfishes, and sometimes on sharks. This species can reach in total length, though most do not exceed . It is an elongated cylindrical fish, usually whitish or pale blue in life, but tan or dusky-brown when dead. The rather flattened head has an oblong disc or sucker with 14 to 17 transverse plates with which it

pos: Common remora in aquaria. Remoras have been used in fishing. Humans may attach fishing line to the remora and wait for it to cling to a larger fish. Other common names for this familiar fish include suck fish, stout sucking fish, common sucker, shark-sucker, brown sucker, and shark pilot. Common remora The common remora ("Remora remora") is a pelagic marine fish belonging to family Echeneidae. The dorsal fin, which has 22 to 26 soft rays, acts as a suction cup, creating a vacuum to allow it to attach to larger marine animals, such as whales, dolphins, sharks, and sea turtles. The common

pos: Animal locomotion or it can release itself by swimming forward. Remoras sometimes attach to small boats. They swim well on their own, with a sinuous, or curved, motion. When the remora reaches about , the disc is fully formed and the remora can then attach to other animals. The remora's lower jaw projects beyond the upper, and the animal lacks a swim bladder. Some remoras associate primarily with specific host species. They are commonly found attached to sharks, manta rays, whales, turtles, and dugongs. Smaller remoras also fasten onto fish such as tuna and swordfish, and some small remoras travel in the

pos: Remora can then attach to other animals. The remora's lower jaw projects beyond the upper, and the animal lacks a swim bladder. Some remoras associate with specific host species. They are commonly found attached to sharks, manta rays, whales, turtles, and dugongs (hence the common names "sharksucker" and "whalesucker"). Smaller remoras also fasten onto fish such as tuna and swordfish, and some small remoras travel in the mouths or gills of large manta rays, ocean sunfish, swordfish and sailfish. The relationship between a remora and its host is most often taken to be one of commensalism, specifically phoresy. Research into the

pos: Common remora Common remora The common remora ("Remora remora") is a pelagic marine fish belonging to family Echeneidae. The dorsal fin, which has 22 to 26 soft rays, acts as a suction cup, creating a vacuum to allow it to attach to larger marine animals, such as whales, dolphins, sharks, and sea turtles. The common remora has a suckerlike dorsal fin and an anal fin. Its body can be brown, black or grey in color. This species can reach in total length, though most do not exceed . The maximum known weight of this species is . "R. remora" and its host

neg: Sharks in captivity fish, puffers, and wrasses can all injure them. A large grouper is capable of consuming smaller sharks. Sometimes docile bottom feeding sharks are put at risk because of the fish that feed on the ocean bottom, sedentary sharks are simply an extension of the substrate." Another problem aquarists keeping sharks with other types of fish have encountered is that the smaller, more passive aquarium-friendly shark species often have difficulty competing with their tankmates for the food provided by the aquarist. Sharks are predatory themselves and may maul or consume tankmates smaller or weaker than themselves. Sharks in captivity Several species

neg: Copepod of human carbon emissions, thus reducing their impact. Many planktonic copepods feed near the surface at night, then sink (by changing oils into more dense fats) into deeper water during the day to avoid visual predators. Their moulted exoskeletons, faecal pellets, and respiration at depth all bring carbon to the deep sea. About half of the estimated 13,000 described species of copepods are parasitic and have strongly modified bodies. They attach themselves to bony fish, sharks, marine mammals, and many kinds of invertebrates such as molluscs, tunicates, or corals. They live as endo- or ectoparasites on fish or invertebrates in

neg: Pain in fish that the absence of C-type fibres in cartilagenous sharks and rays indicates that signalling leading to pain perception is likely to be impossible, and the low numbers for bony fish (e.g. 5% for carp and trout) indicate this is also highly unlikely for these fish. Rose concludes there is little evidence that sharks and rays possess the nociceptors required to initiate pain detection in the brain, and that, while bony fish are able to unconsciously learn to avoid injurious stimuli, they are little more likely to experience conscious pain than sharks. A-delta-type fibres, believed to trigger avoidance reactions, are common

neg: Fencepost limestone attach to such shells, could thrive on this bottom. Consequently, the floor itself was frequently covered with mollusks, especially species of "Inoceramus", ranging in size from few millimeters to well over a meter, themselves encrusted with oysters. There were several species of free-swimming ammonites, Baculites, and belemnites, which serve as index fossils within the members of the Greenhorn and Carlile formations. Abundant fish populations of the Greenhorn sea supported the largest of predators; great fish, sharks, and reptiles alike, including plesiosaurs, mosasaurs, elasmosaurs, and "Xiphactinus". More than any other rock bed in of the lower Colorado Group, the Fencepost makes

neg: Thresher shark and cuttlefish are the primary food items of the thresher sharks. They are known to follow large schools of fish into shallow waters. Crustaceans and occasionally seabirds are also taken. Thresher sharks are solitary creatures which keep to themselves. It is known that thresher populations of the Indian Ocean are separated by depth and space according to sex. Some species however do occasionally hunt in a group of two or three contrary to their solitary nature. All species are noted for their highly migratory or oceanodromous habits. When hunting schooling fish, thresher sharks are known to "slap" the water, herding

neg: Pilot fish Money", during a conspiracy to entrap Moist von Lipwig, Heretofore reflects on his current predicament and uncomfortable relationship with Cosmo Lavish and says "Does he think he's Vetinari? What do they call those fishes that swim alongside sharks, making themselves useful so they don't get eaten? That's me, that's what I'm doing, just hanging on, because it's much safer than letting go." Ernest Hemingway bitterly immortalised John Dos Passos as a "pilot fish" for the wealthy in "A Moveable Feast", after falling out with him over the Spanish Civil War. Pilot fish The pilot fish ("Naucrates ductor") is a carnivorous

neg: Ectosymbiosis found frequently in organisms that attach themselves to larger species in order to move long distances or scavenge food easily; this is documented in remoras which attach to sharks to scavenge and travel. An additional ectosymbiotic example of commensalism is the relationship between small sessile organisms and echinoids in the Southern ocean, where the echinoids provide substrate for the small organisms to grow and the echinoids remain unaffected. "Main article:" Mutualism Mutualism is a form of ectosymbiosis where both the host and parasitic species benefit from the interaction. There are many examples of mutualistic ectosymbiosis that occur in nature. One

neg: Land-based game fishing belief that anglers attract sharks closer to shore or use chum to catch sharks. This belief is inaccurate though as the mechanics of wave and water currents do not lend themselves to effective use of chumming and baits used are not significantly larger or different than what is already present in the water naturally. Effective chumming involves spreading a long trail of significant amounts of fish blood and oils through a current to create a scent line. These trails often need to be miles long to become effective as they still require a shark to initially swim through the chum

neg: Hemibdella soleae fish lay eggs on the seabed in locations where the fish like to semi-bury themselves in the sediment; the eggs have stalks and are anchored to grains of sand. The free-swimming larvae search out a host fish and attach to the anterior end of the dorsal surface, the only part of the fish not buried in sediment. After a short period of development, the larvae migrate to the ventral surface of the fish. Here they attach to the host with their front sucker oriented towards the front of the fish. Hemibdella soleae Hemibdella soleae is a marine species of leech

neg: Tracheliastes polycolpus Tracheliastes polycolpus Tracheliastes polycolpus is a copepod ectoparasite of a number of freshwater fish in Western Europe, including "Leuciscus burdigalensis", the beaked dace. The parasite attaches itself to the fins of the host, and lives on the mucus and epithelial cells of the host. "T. polycolpus" find fish and attach themselves primarily onto the fins. The female "T. polycolpus" prefer to attach themselves onto the anal and pelvic fins. After attaching themselves onto the fish, they feed on their epithelial cells and mucus on the host. Then find a new host to feed on afterwards. Eggs attached onto the surface

neg: Silvertip shark Individual silvertip sharks behave very aggressively towards one another, and many are heavily scarred. They are also reported to dominate Galapagos sharks ("C. galapagensis") and blacktip sharks ("C. limbatus") of equal size when competing for food. This shark sometimes forms mixed-species aggregations with grey reef sharks. Rainbow runners ("Elagatis bipinnulata") have been observed rubbing against silvertip sharks, using the sharks' rough skin to scrape off parasites. They sometimes follow marine mammals such as bottlenose dolphins ("Tursiops" sp.) in open water, and are themselves followed by pilot fish ("Naucrates ductor"). Like the grey reef shark, the silvertip shark sometimes perform a

neg: Fish physiology some species able to detect as little as one part per million of blood in seawater. Sharks have the ability to determine the direction of a given scent based on the timing of scent detection in each nostril. This is similar to the method mammals use to determine direction of sound. They are more attracted to the chemicals found in the intestines of many species, and as a result often linger near or in sewage outfalls. Some species, such as nurse sharks, have external barbels that greatly increase their ability to sense prey. Some fish, such as catfish and sharks,

neg: American alligator alligators have recently been filmed and documented killing and eating sharks and rays; four incidents documented indicated that bonnetheads, lemon sharks, Atlantic stingrays and nurse sharks are components of the animal's diet. Sharks are also known to prey on American alligators in turn, indicating encounters between the two predators are more common than thought. American alligators will occasionally prey on large mammals, such as deer, but will usually do so when fish and smaller prey levels go down. Rarely, American alligators have been observed killing and eating bobcats, but such events are not common and have little effect on bobcat

neg: Grey reef shark the silvertip shark. At Rangiroa Atoll in French Polynesia, great hammerheads ("Sphyrna mokarran") feed opportunistically on grey reef sharks that are exhausted from pursuing mates. Known parasites of this species include the nematode "Huffmanela lata" and several copepod species that attach to the sharks' skin, and juvenile stages of the isopods "Gnathia trimaculata" and "G. grandilaris" that attach to the gill filaments and septa (the dividers between each gill). Grey reef sharks feed mainly on bony fishes, with cephalopods such as squid and octopus being the second-most important food group, and crustaceans such as crabs and lobsters making up the

neg: Pacific spiny dogfish rays. Dogfish are carnivorous or meat eaters. Their teeth are sharp and are inclined laterally in order to cut through their prey. The Pacific dogfish usually eat on mollusks or crustaceans such as squid, krill, and shrimp. They also eat other small sharks and fish. According to Jennifer Bigman, a marine scientist, there is no difference between what male dogfish eat versus what female dogfish eat. Their prey are usually found on the sea floor, so the Pacific spiny dogfish has to scan the bottom in order to invest in their prey. Elasmobranchs consume very little carbohydrates and glucose. During

neg: Crayfish water and "outcompeted the native clearwater crayfish." Other studies confirmed that transporting crayfish to different environments have led to various ecological problems, including the elimination of native species. Transporting crayfishes as live bait has also contributed to the spread of zebra mussels in various waterways throughout Europe and North America, as they are known to attach themselves to exoskeleton of crayfishes. Crayfish are kept as pets in freshwater aquariums, typically with bluegill or bass, rather than goldfish or tropical or subtropical fish. They prefer foods like shrimp pellets or various vegetables, but will also eat tropical fish food, regular fish

neg: Suckermouth breathe without using its mouth. Additionally many other fish of the order Cypriniformes have developed a sucking ability to a lesser or greater extent: In general many benthic dwelling or feeding fish will have a suckermouth feature. Many of these fishes originate from fast-moving waters, where the sucker allows the fish to 'stick' itself down without too much difficulty. Whilst all these fish have a limited sucking ability – they are able to swallow their food – it is not necessarily correct to assume that they can attach themselves to a submerged object by suction; though their behaviour may give

neg: Little tunny Pigmentation in the eyes appear 48 hours after hatching. The teeth and fins develop at sizes of 3.7–14 mm. Once the larvae are 14 mm to 174 mm long, they take on the adult appearance; the body becomes more elongated. Studies have found that it takes approximately 3 years for the little tunny's gonads to reach sexual maturity. The average size of a sexually mature individual is in fork length. Bony fish, Marlins, sea birds, sharks, and rays prey on the little tunny. Other tunas, including conspecifics and yellowfin tuna ("Thynnus albacares") are predators of the little tunny. Fish such

neg: Alebrije price of each piece depends on the quality, coloring, size, originality and sometimes the reputation of the carver. The most expensive pieces are most often sent abroad. Pieces sold retail in Oaxaca generally range from US$1 to $200. The most commercialized figures are those of dogs, armadillos, iguanas, giraffes, cats, elephants, zebras, deer, dolphins, sharks and fish. Animals are often painted with bright colors and designs and carved with exaggerated features that bear little resemblance to what occurs in the natural world. Anthropomorphism is common and carvings of animals playing musical instruments, golfing, fishing, and engaging in other human pursuits

neg: Bivalvia attach and trigger a tissue response that forms a small cyst around each larva. The larvae then feed by breaking down and digesting the tissue of the fish within the cysts. After a few weeks they release themselves from the cysts and fall to the stream bed as juvenile molluscs. The fish are relatively unharmed. Brachiopods are shelled marine organisms that superficially resembled bivalves in that they are of similar size and have a hinged shell in two parts. However, brachiopods evolved from a very different ancestral line, and the resemblance to bivalves only arose because of a similar lifestyle.

neg: Centrophoridae Centrophoridae The Centrophoridae are a family of squaliform sharks. The family contains just two genera and about 15 species. They are sometimes called gulper sharks, but this is also the name of a specific species in the family, "Centrophorus granulosus". These are generally deepwater fish. While some, such as the gulper shark "C. granulosus", are found worldwide and fished commercially, others are uncommon and little-known. Their usual prey is other fish; some are known to feed on squid, octopus, and shrimp. Some species live on the bottom (benthic), while others are pelagic. They are ovoviviparous, with the female retaining the

neg: Hydrichthys sarcotretis Hydrichthys sarcotretis Hydrichthys sarcotretis is a species of colonial marine hydrozoans now included in the family Pandeidae. The polyps of members of this genus are parasitic and attach themselves to a fish. "H. sarcotretis" is a species that exhibits hyperparasitism by attaching itself to a copepod, itself the parasite of a fish. In "H. sarcotretis", parasitism is taken a stage further when the hydrozoan attaches itself to the copepod "Cardiodectes medusaeus". This is itself an ectoparasite of the Northern lampfish ("Stenobrachius leucopsarus") in the family Myctophidae. The copepod attaches itself to the bulbus arteriosus of the fish. Such a parasitic

neg: Hydrichthys sarcotretis chain is known as hyperparasitism. The actions of the copepod castrate its fish host. Both male and female fish do not reproduce and seem to grow faster when attacked by the copepod and it seems to have a negligible energy demand from them. The hydrozoan parasite castrates the copepod, a process called hypercastration. Hydrichthys sarcotretis Hydrichthys sarcotretis is a species of colonial marine hydrozoans now included in the family Pandeidae. The polyps of members of this genus are parasitic and attach themselves to a fish. "H. sarcotretis" is a species that exhibits hyperparasitism by attaching itself to a copepod, itself

neg: Aquatic locomotion complemented by a rearward force, side forces which are wasted portions of energy, and a normal force that is between the forward thrust and side force. Different fish swim by undulating different parts of their bodies. Eel-shaped fish undulate their entire body in rhythmic sequences. Streamlined fish, such as salmon, undulate the caudal portions of their bodies. Some fish, such as sharks, use stiff, strong fins to create dynamic lift and propel themselves. It is common for fish to use more than one form of propulsion, although they will display one dominant mode of swimming Gait changes have even been

neg: Krøyer's deep sea angler fish Krøyer's deep sea angler fish Krøyer's deep sea angler fish ("Ceratias holboelli") is a species of fish in the family Ceratiidae, the sea devils. This deep-sea anglerfish is found in all oceans, at depths of , but mainly between . Females typically are long, but can reach . The much smaller males only reach and they are symbiotic, as they attach themselves to a female. The species' scientific epithet commemorates Carl Peter Holbøll, a Danish civil servant and early explorer of the fauna of Greenland. Several specimens have been found in the stomachs of sperm whales caught in the Azores

neg: Krøyer's deep sea angler fish and in the Antarctic. Other common names include longray seadevil and northern seadevil. Krøyer's deep sea angler fish Krøyer's deep sea angler fish ("Ceratias holboelli") is a species of fish in the family Ceratiidae, the sea devils. This deep-sea anglerfish is found in all oceans, at depths of , but mainly between . Females typically are long, but can reach . The much smaller males only reach and they are symbiotic, as they attach themselves to a female. The species' scientific epithet commemorates Carl Peter Holbøll, a Danish civil servant and early explorer of the fauna of Greenland. Several specimens

neg: Fish fin keeping an upright position or stopping. Most fish use fins when swimming, flying fish use pectoral fins for gliding, and frogfish use them for crawling. Fins can also be used for other purposes; male sharks and mosquitofish use a modified fin to deliver sperm, thresher sharks use their caudal fin to stun prey, reef stonefish have spines in their dorsal fins that inject venom, anglerfish use the first spine of their dorsal fin like a fishing rod to lure prey, and triggerfish avoid predators by squeezing into coral crevices and using spines in their fins to lock themselves in place.

neg: Night shark activity occurs at night, hence its common name, with peaks at dawn and dusk. Catch records indicate that this species is usually found in schools and conducts a diel vertical migration, spending the day at a depth of and moving up to shallower than at night. Ovulating and gravid females are rarely ever caught, suggesting that during this period they may stop feeding or segregate themselves from others of their species. Potential predators of the night shark include larger sharks. Known parasites include the copepods "Kroyeria caseyi", which attach to the gills, "Pandarus bicolor" and "P. smithii", which infest the

neg: Piscicolidae respect to the genus "Oxytonostoma". The Piscicolidae are parasitic on the blood of fishes. Some species are host specific while others can accept a larger range of hosts. Some, such as the European "Piscicola geometra", take a blood meal and then drop off the host and hide somewhere while they digest the blood; some, mostly in marine or estuarine habitats with soft substrates, attach themselves temporarily to a crustacean after leaving their fish host; others remain attached to a fish semi-permanently. Leeches are hermaphrodites and mating may take place on or off the fish host, but in either case, the

neg: North Carolina Aquariums the Indian and Pacific Oceans, but in 2000 were confirmed as having established themselves in North Carolina. Australian spotted jellies, recently invasive in U.S. coastal waters, are among the gallery's newer exhibits. In June 2012, the aquarium opened the Bamboo Shark Touch Pool exhibit which allows visitors to touch live bamboo sharks. Bamboo sharks are considered harmless to humans and the aquarium hopes to educate visitors about sharks through interaction. The Pacific Reef Display features living corals, giant clam, anemones, cardinalfish, hawkfish, clownfish, wrasses, surgeonfish, and nearly a dozen other fish species. The facility closed in November 1999 for a

neg: Papilla (fish anatomy) Papilla (fish anatomy) The papilla, in certain kinds of fish, particularly rays, sharks, and catfish, are small lumps of dermal tissue found in the mouth, where they are "distributed uniformly on the tongue, palate, and pharynx". They "project slightly above the surrounding multi-layered epithelium", and the taste buds of the fish are "situated along the crest or at the apex of the papillae". Unlike humans, fish have little or nothing in the way of a tongue, and those that have such an organ do not use it for tasting, but merely for cushioning the mouth and manipulating things within it.

neg: Variations of the ichthys symbol fish and inscribe "Darwin" in the body. Others make reference to sushi, sharks, the food chain, fast food, the devil or death. How are we to interpret these variations? These adaptations are themselves susceptible to multiple interpretations, ranging from humour to critique, to mocking derision, to blasphemy." Among such parodies are the "Darwin fish", often displayed by "atheists and freethinkers" in the United States, and the "Fish-hungry shark", displayed by Muslims in Egypt. The Darwin fish is a fish symbol with "evolved" legs and feet attached, and often with the word "Darwin" inside (like the ΙΧΘΥΣ or Jesus found in

neg: Carolina heelsplitter stream. Soon afterwards the sperm is taken in by the females, a process which is called siphoning. The female's eggs, which will be carried in the females gills, are then fertilized. When the glochidia (larvae) are fully developed, the female mussel releases them into the water. The larvae must attach themselves quickly to a body part of their host fish, which is not harmed in the process. The host fish species for this mussel is still unknown. Attached to the fish, the heelsplitters receive oxygen and other needs from the host for several weeks. When they have grown into fully

neg: Fish physiology fertilisation 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

neg: Raymond W. Gibbs Jr. as resemblance metaphors which are in the form of “A is B” are seen as expressing common characteristics between the A and the B in the form “A is B”. For example, “lawyers are sharks” is not meant to be taking literally as lawyers are predatory fish that live in the ocean. But as a way to infer that lawyers and sharks share the same qualities such as aggressiveness, and ceaseless effort to attain their goals with little regard to others in their path. But these metaphorical statements can do more than just assert a meaning. Gibbs says that they

neg: Pregnancy in fish types of viviparity among fish. Examples of ovoviviparous fish are many of the squaliform sharks, which include sand sharks, mackerel sharks, nurse sharks, requiem sharks, dog sharks and hammerheads, among others, and the lobe finned coelacanth. Some species of rockfish ("Sebastes") and sculpins (Comephoridae) produce rather weak larvae with no egg membrane and are also, by definition, ovoviviparous. Ovoviviparity occurs in most live-bearing bony fishes (Poeciliidae). Viviparous fish include the families Goodeidae, Anablepidae, Jenynsiidae, Poeciliidae, Embiotocidae and some sharks (some species of the requiem sharks, Carcharinidae and the hammerheads, Sphyrnidae, among others). The halfbeaks, Hemiramphidae, are found in both marine

neg: Great hammerhead pectoral fins and swimming in a stiff or jerky fashion. Juveniles are preyed upon by larger sharks such as bull sharks ("Carcharhinus leucas"), while adults have no major predators except for killer whales, who hunt hammerheads of any age. Yellow jacks ("Carangoides bartholomaei") have been seen rubbing themselves against the hammerhead's flanks, possibly to rid themselves of parasites. Schools of pilot fish ("Naucrates ductor") sometimes accompany the great hammerhead. The great hammerhead is parasitized by several species of copepods, including "Alebion carchariae", "A. elegans", "Nesippus orientalis", "N. crypturus", "Eudactylina pollex", "Kroyeria gemursa", and "Nemesis atlantica". An active predator with a

neg: Bait fish but adapted for use in a different context. Bait fish are consumed by larger, aquatic predators. Swimming in ocean water with bait fish can be dangerous, as these fish attract sharks. Bait fish will sometimes use whale sharks as a shield from their other predators such as tuna, as tuna are usually wary of approaching the sharks. The shark cannot attack the bait fish easily, as they constantly swim above them and are too fast for the shark to manoeuvre its mouth into position. However, the sharks eventually dive deep, where the bait fish cannot follow, and as the other

neg: Fish 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

neg: Cymothoidae Cymothoidae The Cymothoidae are a family of isopods in the suborder Cymothoida and are found in both marine and freshwater environments. Cymoithoids are ectoparasites, usually of fish, and among their number they include the bizarre "tongue-biter" ("Cymothoa exigua") which attaches to a fish's tongue causing it to atrophy, and replaces the tongue with its own body. Around 40 genera and more than 380 species of cymothoid are recognised. Cymothoids exhibit various adaptations to their carnivorous or parasitic lifestyles. As juveniles, they are not specific in their requirements and attach themselves temporarily to the skin of any fish. They produce anticoagulants

neg: Bigeyed sixgill shark off New Caledonia, South Pacific Ocean. Little is known about the feeding habits of the bigeyed sixgill. Based on the few stomach examinations of these sharks, they are thought to feed mainly on small to moderately sized bony fish and crustaceans. Like all sharks of the order Hexanchiformes found so far, this shark is ovoviviparous, meaning the eggs are retained inside the female's body until hatching. The bigeyed sixgill, after an unknown gestation period, gives birth to litters of up to 13 pups. Because of the size of this shark, their main predators probably are larger sharks. Like many deepwater

neg: Blacktip shark attains a length of . Swift, energetic piscivores, blacktip sharks are known to make spinning leaps out of the water while attacking schools of small fish. Their demeanor has been described as "timid" compared to other large requiem sharks. Both juveniles and adults form groups of varying size. Like other members of its family, the blacktip shark is viviparous; females bear one to 10 pups every other year. Young blacktip sharks spend the first months of their lives in shallow nurseries, and grown females return to the nurseries where they were born to give birth themselves. In the absence of

neg: Sillaginidae Their main aquatic predators are a wide variety of larger fish, including both teleosts and a variety of sharks and rays. Marine mammals including seals and dolphins have been reported to have taken sillaginids as a main food source. Seabirds are also another major predator of the family, with diving species such as Cormorants taking older fish in deeper waters while juvenile fish in shallow water fall prey to wading birds. Sillaginids are often called 'sandborers' due to their habit of burying themselves in the substrate to avoid predators, much in the same way as they forage, by ploughing their

neg: Bowfishing Bowfishing Bowfishing is a method of fishing that uses specialized archery equipment to shoot and retrieve fish. Fish are shot with a barbed arrow that is attached with special line to a reel mounted on the bow. Some freshwater species commonly hunted include common carp, grass carp, bighead carp, alligator gar, and paddlefish. In saltwater, rays and sharks are regularly pursued. Bows are usually very simple. Most do not have sights, and aiming is by line-of-sight judgment down the arrow. There are a couple of types of rests including the hook and roller rest. Most bows have little to no

neg: Halfbeak Halfbeak The halfbeaks, also called spipe fish or spipefish (family Hemiramphidae) are a geographically widespread and numerically abundant family of epipelagic fish inhabiting warm waters around the world. The halfbeaks are named for their distinctive jaws, in which the lower jaws are significantly longer than the upper jaws. The similar viviparous halfbeaks (family Zenarchopteridae) have often been included in this family. Though not commercially important themselves, these forage fish support artisanal fisheries and local markets worldwide. They are also fed upon by other commercially important predatory fishes, such as billfishes, mackerels, and sharks. In 1775, Carl Linnaeus was the first

neg: Sensory systems in fish duct (which is not fused, unlike bony fish) between the anterior and posterior nasal openings, with some species able to detect as little as one part per million of blood in seawater. Sharks have the ability to determine the direction of a given scent based on the timing of scent detection in each nostril. This is similar to the method mammals use to determine the direction of sound. They are more attracted to the chemicals found in the intestines of many species, and as a result often linger near or in sewage outfalls. Some species, such as nurse sharks, have

neg: Marine pharmacognosy cone snail that has a poisoned harpoon-like projectile which it uses to paralyze prey like small fish. Some organisms, like the Viperfish, are believed to attract small fish or prey by using its photophore. Many different marine organisms have been explored for bioactive compounds. Some vertebrate animals include fish, sharks and snakes. Some examples of invertebrates are sponges, coelenterates, tunicates, echinoderms, corals, algae, molluscs and bryozoans. Some microorganisms include bacteria, fungi and cyanobacteria. There is an ongoing debate on what organisms are the actual true producers of some compounds. About 40% of the biomass of sponges can be from microorganisms.

neg: Little tunny albacore, or little tuna, it resembles the Atlantic bonito, skipjack tuna, and species of mackerel. The little tunny feeds primarily on pelagic fish. It is best identified by the dark spots appearing between its pectoral and ventral fins and "worm-like" markings on its back. Commercially, the fish is used as bait for sharks and marlin due to its high oil content and hook retention. It is considered by many to be a trash fish because it has a darker and stronger taste than that of the other tunas. Ciguatera poisoning related to its consumption has even been reported. However, the

neg: Sucker (zoology) fish family the Catostomidae are known as "suckers". These fish have a suckermouth. Certain species of bats such as Madagascar sucker-footed bat and Western sucker-footed bat, are generally called "sucker-footed bats" because of suckers on their limbs. They are members of the family Myzopodidae and endemic to Madagascar. They have small cups of suckers on their wrists and ankles. They roost inside the rolled leaves of palm trees, using their suckers to attach themselves to the smooth surface. Sucker (zoology) A sucker in zoology refers to specialised attachment organ of an animal. It acts as an adhesion device in parasitic

neg: Plesiomorphy and symplesiomorphy relationships within that tree. A famous example is the trait of breathing via gills in bony fish and cartilaginous fish. Bony fish are more closely related to terrestrial vertebrates, which evolved out of a clade of bony fishes that breathe through their skin or lungs, than they are to sharks, rays, and other cartilaginous fish. Their kind of gill respiration is shared by the "fishes" because it was present in their common ancestor and lost in the other living vertebrates. The shared trait cannot treated as evidence that bony fish are more closely related to sharks and rays than they

neg: Glyptothorax to greatly depressed. The skin is either smooth or tuberculate. The eyes are small and dorsally placed. The lips are thick, fleshy and often papillate. The maxillary barbels have a well-developed membrane and a soft base. The gill openings are wide. The paired fins are plaited and modified to form an adhesive apparatus in some species of "Glyptothorax". Like other sisorids, these fish are rheophilic, that is they inhabit fast-flowing streams, where they are adapted to live by using the adhesive apparatus on the underside to attach themselves to rocks and prevent being washed away. There are currently 103 recognized

neg: Winged mapleleaf the St. Croix River is the only one that has been proven to actually be reproducing and growing in population. The mussels in the other 3 locations have no evidence that their populations are growing or that there is actually offspring is being produced. It is currently estimated that there is somewhere between 50-1000 individuals that are still alive today. The mussel filters out tiny food particles, either phytoplankton or zooplankton. The young winged mapleleafs attach themselves to the gills of a host fish for feeding and growing purposes until they reach the stage in their life cycle that they

neg: Animals of Devonian Michigan ancient fish dating back the late Silurian period, often being called spiny sharks. Although they are not true sharks, they had spines on all of their fins, an important defensive adaptation. They were some of the first fish to evolve jaws, and their fossils are extremely rare. They are nearly impossible to find anywhere, and are not very well understood. They became extinct at the end of the Devonian period that also claimed the Placoderms and most other jaw-less fish. Sharks first appeared in the mid Devonian period, and are extremely rare to find anywhere. A variety of teeth from

neg: Epaulette shark Epaulette sharks are almost all parasitized by the praniza (parasitic) larval stage of gnathiid isopods. The larvae feed on blood and mostly attach to the skin around the cloaca and the claspers, though they are also found inside the mouth and on the gills. These parasites cause little damage and are not believed to adversely affect the health of the shark. Other parasites of this species include a species of myxosporean in the genus "Kudoa", which infests the skeletal muscles, the hemogregarine protozoan "Haemogregarina hemiscyllii", which infects the blood, the ostracod "Sheina orri", which attaches to the gills, and the

neg: Paleontology in North Carolina during 2008, found in cores drilled offshore by the U.S. Army Corps of Engineers. During the Eocene, between 38 and 54 million years ago, North Carolina was home to marine life. Some of their remains are preserved in what are now the marl pits in Pender County. Among the invertebrates were nautiloids, sand dollars, and sea urchins. The vertebrates included bony fish, sharks, and whales. These deposits are relatively well known. Sharks found in the state include early Tiger and Mako sharks. Despite their renown, North Carolina's Eocene fossils are generally poorly preserved. Other invertebrates of this epoch included at

neg: Little sleeper shark the Azores. These threats are compounded by the fact that, like other Squaloid sharks, the Little Sleeper shark is likely to be slow to mature, and the relatively small range of the fish. Although no species-specific conservation measures are in place, the General Fisheries Commission for the Mediterranean has banned bottom trawling below depths of 1000m. More information is needed on the species before detailed protection can be brought in to action. Little sleeper shark The little sleeper shark ("Somniosus rostratus") is a sleeper shark of the family Somniosidae found in the northeast Atlantic, western Mediterranean, and western Pacific around

neg: Flatworm without oxygen for long periods. Members of this small group have either a single divided sucker or a row of suckers that cover the underside. They infest the guts of bony or cartilaginous fish, turtles, or the body cavities of marine and freshwater bivalves and gastropods. Their eggs produce ciliated swimming larvae, and the life cycle has one or two hosts. These parasites attach themselves to their hosts by means of disks that bear crescent-shaped hooks. They are divided into the Monogenea and Cestoda groupings. Of about 1,100 species of monogeneans, most are external parasites that require particular host species

neg: Sharks in captivity known to occur in captive sharks that are deficient in some essential vitamin. Vitamin B deficiency results in a treatable condition where the shark's back arches and it swims in a circular motion. Feeding sharks frozen non-marine fish can result in deficiencies of omega-3 fatty acids, which can result in "fat infiltration of the liver," which can impede the organ's function seriously enough for major health issues. Sometimes sharks are unwittingly put in harm's way when aquarists include potentially dangerous tankmates in the same aquarium. Hobbyists generally don't think of other fish being a threat to sharks, but triggerfish, angel

neg: Iridescent shark texture. Recipes for other whitefish such as sole or halibut can be adapted to pangasius. Pangasius is an omnivorous fish, and thus does not require a high level of animal protein in its diet. Typical grading sizes are 3–5 oz, 5–7 oz, and 7–9 oz. While juvenile iridescent sharks are sold as pets for home aquariums, they are not easy fish to keep. While they can survive in a 40-gallon aquarium, iridescent sharks are schooling fish that prefer groups, are accustomed to living in rivers, and are active fish that require space. They have very poor eyesight, so detected movement

neg: Unionidae attach to the gills, fins or skin of a host fish. A cyst is quickly formed around the glochidia, and they stay on the fish for several weeks or months before they fall off as juvenile mussels, which then bury themselves in the sediment. Some of the species in the Unionidae, commonly known as pocketbook mussels, have evolved a remarkable reproductive strategy. The edge of the female's body that protrudes from the valves of the shell develops into an imitation of a small fish complete with markings and false eyes. This decoy moves in the current and attracts the attention

neg: Tuna to more "dolphin friendly" methods, now generally involving lines rather than nets. However, there are neither universal independent inspection programs nor verification of "dolphin safeness", so these protections are not absolute. According to Consumers Union, the resulting lack of accountability means claims of tuna that is "dolphin safe" should be given little credence. Fishery practices have changed to be dolphin friendly, which has caused greater bycatch including sharks, turtles and other oceanic fish. Fishermen no longer follow dolphins, but concentrate their fisheries around floating objects such as fish aggregation devices, also known as FADs, which attract large populations of other

neg: Lanternfish food for many marine animals, lanternfish are an important link in the food chain of many local ecosystems, being heavily preyed upon by whales and dolphins, large pelagic fish such as salmon, tuna and sharks, grenadiers and other deep-sea fish (including other lanternfish), pinnipeds, sea birds, notably penguins, and large squid such as the jumbo squid, "Dosidicus gigas". Lanternfish themselves have been found to feed on bits of plastic debris accumulating in the oceans. At least one lantern fish was found with over 80 pieces of plastic chips in its gut, according to scientists monitoring ocean plastic in the Pacific

neg: Manta ray each week. When foraging, it slowly swims around its prey, herding it into a tight "ball", and then speeds through the bunched organisms with a wide-open mouth. If a ball is particularly dense, a manta may somersault through it. While feeding, mantas flatten their cephalic fins to channel food into their mouths and the small particles are collected by the tissue between the gill arches. As many as 50 individual fish may gather at a single, plankton-rich feeding site. Mantas are themselves preyed upon by large sharks and by killer whales. They may also be bitten by cookiecutter sharks, and

neg: Pelagic fish world harvest in 2005 consisted of 93.2 million tonnes captured by commercial fishing in wild fisheries. Of this total, about 45% were pelagic fish. The following table shows the world capture production in tonnes. In 2009, the International Union for Conservation of Nature (IUCN) produced the first red list for threatened oceanic sharks and rays. They claim that about one third of open ocean sharks and rays are under threat of extinction. There are 64 species of oceanic sharks and rays on the list, including hammerheads, giant devil rays and porbeagle. Oceanic sharks are captured incidentally by swordfish and tuna

neg: Spiral valve extended period maximum nutrient absorption is ensured. For this reason, many sharks and related fish feed very infrequently. The food passes into the comparatively short colon of the shark almost fully digested, and then out the cloaca and vent. A consequence of the spiral valve constricting the lumen of the ileum is that sharks cannot pass large hard objects (such as bones) through their lower intestine. Such objects rather remain in the stomach until sufficiently broken down for passing through the valve region, or are regurgitated. Consequently, shark stomachs often contain items of interest that enable one to determine what

neg: Coral reef fish wide variety of reef-dwelling bony fishes and cephalopods, as well as some elasmobranchs such as eagle rays and yellow stingrays . Young sharks feed on small fishes, shrimps, and crabs. In turn, young sharks are preyed on by larger sharks such as the tiger shark and the bull shark. Coral reef fish Coral reef fish are fish which live amongst or in close relation to coral reefs. Coral reefs form complex ecosystems with tremendous biodiversity. Among the myriad inhabitants, the fish stand out as colourful and interesting to watch. Hundreds of species can exist in a small area of a

neg: Golfo Dulce, Costa Rica crocodiles also inhabit the area. Sharks Several species of sharks live within the gulf; these species include the Whale Shark, Scalloped Hammer-Head, and Rays. Along with sharks, other large fish such as Needle Fish, Dorados, and Marlins also live in the gulf. While Needle Fish are protected, Marlins and Dorados are popular targets for sport fishing. Invertebrates Numerous invertebrates live in the Golfo Dulce; these include jellyfish, Portuguese Man-O-Wars, sea stars, coral reefs, crabs, and sea mollusks. The ecosystem that surrounds the actual Golfo Dulce is just as rich in life as in the water with two to three percent

neg: Climatiiformes Climatiiformes The Climatiiformes is an order of extinct fish belonging to the class Acanthodii. Like most other "spiny sharks", the Climatiiformes had sharp spines. These animals were rather small in size (about 4 in or 10 cm) and lived from the Late Silurian to the Early Carboniferous period. The type genus is "Climatius". The order splits into the suborders Climatiida and Diplacanthida, which themselves split into several families. Climatiiformes is a fish species which is on the verge of extinction. It belongs to kingdom Animalia and class Acanthodii. It has sharp spines on their body also called as “spiny sharks.

neg: Physalia utriculus animals called polyps, which are all connected to each other and function like the organs and tissues of single multicellular organisms, like fish or humans, to the extent that the polyps lack the ability to survive by themselves. It is composed of four separate colonies of polyps and medusoids. The colony consists of a gas-filled polyp that keeps it afloat, and three other polyp types called the gastrozooids, gonozooids and dactylozooids. Dactylozooids form tentacles that hang below the water's surface and detect and attack prey, and drag the prey up towards the gastrozooids (the digestive polyps), which attach their mouths

neg: Euselachii Euselachii Euselachii are an infraclass of a class of cartilaginous fish. This group includes sharks and rays. Of the 14 orders that compose Euselachii, 8 belong to the sharks, 6 to the rays, without an intermediate taxon separating sharks of rays. For this reason, some authors have separated Euselachii in two: super-order Selachimorpha corresponding to orders of sharks; super-order Rajomorphii corresponding to the orders of rays, torpedoes, sawfish and guitar fish. For those who do not recognize these two super-orders, Euselachii therefore has for synonyms Pleurotremata, Selachimorpha and Rajomorphii. Both oviparity and viviparity are found in Euselachii. Around 70% of

neg: Ginglymostomatidae seem to prefer specific haunts and will return to them every day. By night, the sharks are largely solitary; they spend most of their time searching through the bottom sediments in search of food. Their diet consists primarily of crustaceans, molluscs, tunicates, and other fish, particularly stingrays. Nurse sharks are thought to take advantage of dormant fish which would otherwise be too fast for the sharks to catch; although their small mouths limit the size of prey items, the sharks' large throat cavities are used as a sort of bellows valve. In this way, nurse sharks are able to suck

neg: Polyandry in fish Polyandry in fish Polyandry in fish is a mating system where females mate with multiple males within one mating season. This type of mating exists in a variety of animal species. Polyandry has been found in both oviparous and viviparous bony fish and sharks. General examples of polyandry occur in fish species, such as green swordtails and Trinidadian guppies. Specific types of polyandry have also been classified, such as classical polyandry in pipefish cooperative polyandry in cichlids and convenience polyandry in sharks. Poeciliids are freshwater live-bearing fish and internal fertilizers that are able to store sperm for months, setting the

neg: Fish physiology have organs that detect weak electric currents on the order of millivolt. Other fish, like the South American electric fishes Gymnotiformes, can produce weak electric currents, which they use in navigation and social communication. In sharks, the ampullae of Lorenzini are electroreceptor organs. They number in the hundreds to thousands. Sharks use the ampullae of Lorenzini to detect the electromagnetic fields that all living things produce. This helps sharks (particularly the hammerhead shark) find prey. The shark has the greatest electrical sensitivity of any animal. Sharks find prey hidden in sand by detecting the electric fields they produce. Ocean currents

neg: Southern stingray (this helps to explain the stomach contents revealed in the previously mentioned study). To avoid predators, "Dasyatis americana" bury and cover themselves in substrate. Their tails contain venom and are also utilized as protection from predators. Some predators of "Dasyatis americana" are humans and Hammerhead Sharks. In shallow waters, there is a commensal foraging relationship between "Dasyatis americana" fish and Phalacrocorax auritus birds in coastal areas generally like the Gulf of Mexico. When foraging, the "Dasyatis americana" dig through the substrate in search of food; however, this also helps to expose certain other fish hidden in the substrate after which

neg: Photoblepharon palpebratum thereafter. To shut off the light, the eyelight fish uses black lids that slide up to cover the light organs. Use of only a black lid is unique to "Photoblepharon"; the other members of its family either rotate the organ into a pouch or employ a pouch-and-shutter method. The eyelight fish has little interaction with humans. Besides being harmless, it spends the day hidden in rock crevices and so is rarely encountered by divers. It has little commercial value, its primary use being as bait for local fisheries, which will cut out the light organs and attach them to hooks.

neg: Euselachii sharks are viviparous, including some members of Carcharhiniformes such as requiem sharks and hammerhead sharks, while the remaining 30% of sharks as well as all rays are either oviparous or ovoviviparous. Euselachii Euselachii are an infraclass of a class of cartilaginous fish. This group includes sharks and rays. Of the 14 orders that compose Euselachii, 8 belong to the sharks, 6 to the rays, without an intermediate taxon separating sharks of rays. For this reason, some authors have separated Euselachii in two: super-order Selachimorpha corresponding to orders of sharks; super-order Rajomorphii corresponding to the orders of rays, torpedoes, sawfish and

neg: Bivalvia order Unionoida have a different lifecycle. Sperm is drawn into a female's gills with the inhalant water and internal fertilization takes place. The eggs hatch into glochidia larvae that develop within the female's shell. Later they are released and attach themselves parasitically to the gills or fins of a fish host. After several weeks they drop off their host, undergo metamorphosis and develop into juveniles on the substrate. An advantage of this to the molluscs is that they can disperse upstream along with their temporary hosts, rather than being constantly swept downstream by the water flow. Some of the species

neg: Little tunny as the dolphin fish ("Coryphaena hippurus"), wahoo ("Acanthocybium solandri"), Atlantic sailfish ("Istiophorus albicans"), swordfish ("Xiphias gladius"), and various sharks as well as other large marine carnivores all prey on the little tunny. Among those sharks is the whale shark, which feeds on the little tunny's recently spawned eggs. Seabirds prey on small little tunny. Parasites of the little tunny include the copepods Caligus bonito, Caligus coryphaenae, and Caligus productus, all found on the body surface as well as on the wall of the branchial cavities. Another copepod, Pseudocycnoides appendiculatus, has been documented as parasitic on the gill filaments. Other parasites

neg: Sawshark learn more about the deep sea dweller. They are located near Cuba, Florida, and the Bahamas (hence their name) where they dwell in the depths of 400–1000 m. As far as their appearance they can be identified by their snouts with teeth which appear as a saw, as well as their length, they are averaged at 80 cm in length. Saw sharks and sawfish are cartilaginous fish possessing large saws. These are the only two fish that have a long blade-like snout. Although they are similar in appearances, saw sharks are distinct from sawfish. Sawfish are not sharks, but a

neg: Little cormorant tidal estuaries. Little cormorants tend to forage mainly in small loose groups and are often seen foraging alone. They swim underwater to capture their prey, mainly fish. A study in northern India found that the little cormorant fished in water which was less than a metre deep and captured fishes of about length. They propel themselves underwater using their webbed feet. Captured fishes are often brought up to the surface to swallow them and during this time other birds including other little cormorants, painted storks, gulls and egrets may attempt to steal them. Indian cormorants tend to fish communally in

neg: Osteichthyes ocean sunfish, giant grouper, and all the other giant bony fishes alive today. Cartilaginous fishes can be further divided into sharks, rays and chimaeras. In the table below, the comparison is made between sharks and bony fishes. For the further differences with rays, see sharks versus rays. Osteichthyes Osteichthyes (), popularly referred to as the bony fish, is a diverse taxonomic group of fish that have skeletons primarily composed of bone tissue, as opposed to cartilage. The vast majority of fish are members of Osteichthyes, which is an extremely diverse and abundant group consisting of 45 orders, and over 435

neg: Sherman's Lagoon indifference or coldness, as much of the plot revolves around what Sherman and Megan are going to eat for dinner. For instance, one comic had Megan declaring she was in the mood for Italian and the two sharks immediately sought to find an Italian swimming in the water. Also, a large group of tourists swimming in the lagoon is referred to as 'the buffet'. Poodles are regarded as a delicacy, and Sherman regularly eats smaller fish that swim by. One strip saw a fish committing suicide by swimming into Sherman's mouth while he yawned. Characters have also been seen going

neg: Fish jaw are relatively plate-like bones, forming only the sides of the upper jaw, and part of the face, with the premaxilla also forming the lower boundary of the nostrils. Cartilaginous fish, such as sharks and rays also lack a true maxilla. Their upper jaw is instead formed from a cartilagenous bar that is not homologous with the bone found in other vertebrates. Some fish have permanently protruding upper jawbones called rostrums. Billfish (marlin, swordfish and sailfish) use rostrums (bills) to slash and stun prey. Paddlefish, goblin sharks and hammerhead sharks have rostrums packed with electroreceptors which signal the presence of prey

neg: Chimaera Chimaera Chimaeras are cartilaginous fish in the order Chimaeriformes, known informally as ghost sharks, rat fish, spookfish or rabbit fish; the latter three names are not to be confused with rattails, Opisthoproctidae or Siganidae, respectively. At one time a "diverse and abundant" group (based on the fossil record), their closest living relatives are sharks, though their last common ancestor with sharks lived nearly 400 million years ago. Today, they are largely confined to deep water. Chimaeras live in temperate ocean floors down to deep, with few occurring at depths shallower than . Exceptions include the members of the genus "Callorhinchus",

neg: Wa-Tor Wa-Tor Wa-Tor is a population dynamics simulation devised by Alexander Keewatin Dewdney and presented in the December 1984 issue of Scientific American in a 5-page article entitled "Computer Recreations: Sharks and fish wage an ecological war on the toroidal planet Wa-Tor". Wa-Tor is usually implemented as a two-dimensional grid with three colours, one for fish, one for sharks and one for empty water. If a creature moves past the edge of the grid, it reappears on the opposite side. The sharks are predatory and eat the fish. Both sharks and fish live, move, reproduce and die in Wa-Tor according to

neg: Panaque male and female "Panaque" develop bristles, known as odontodes, on the side of head immediately before and onto the pectoral fins. Unlike predatory catfish, these omnivorous catfish have very short barbels. These barbels can be seen in the photograph of mouth of a "Panaque" shown here; they are the short pointed structures on either side of a suckermouth. This sucker-like mouth allows them to attach to rocks and remain stationary with very little expenditure of energy. Along with the species of the "Hypostomus cochliodon" group (formerly the genus "Cochliodon"), it has been argued that "Panaque" are the only fish that

neg: Marine habitats tiny crustaceans that are the most numerous animals on Earth. Other types of zooplankton include jelly fish and the larvae of fish, marine worms, starfish, and other marine organisms". In turn, the zooplankton are eaten by filter-feeding animals, including some seabirds, small forage fish like herrings and sardines, whale sharks, manta rays, and the largest animal in the world, the blue whale. Yet again, moving up the foodchain, the small forage fish are in turn eaten by larger predators, such as tuna, marlin, sharks, large squid, seabirds, dolphins, and toothed whales. The deep sea starts at the aphotic zone, the

neg: Fish reproduction gymnovaries are found in salmonids and a few other teleosts. The eggs of fish and amphibians are jellylike. Cartilagenous fish (sharks, skates, rays, chimaeras) eggs are fertilized internally and exhibit a wide variety of both internal and external embryonic development. Most fish species spawn eggs that are fertilized externally, typically with the male inseminating the eggs after the female lays them. These eggs do not have a shell and would dry out in the air. Even air-breathing amphibians lay their eggs in water, or in protective foam as with the Coast foam-nest treefrog, "Chiromantis xerampelina". Male cartilaginous fishes (sharks and

neg: Brown fur seal to 70% fish, 20% squid, and 2% crab. Also eaten are other crustaceans, cephalopods and sometimes birds. In rare instances, they have even been documented attacking and eating sharks. A recent incident occurred off Cape Point, South Africa, where a large male was observed attacking and killing five blue sharks between 1.0 and 1.4 m long. Observers concluded that the seal likely killed the sharks to eat the fish-rich contents of their stomachs, as well as their livers as a source of energy. The Australian fur seal mostly eats squid, octopus, fish, and lobsters. The brown fur seal dives for

neg: Scallop again. The main causes for the decline seem to be fishing, climate effects, disease, pollutants, and sediment runoff from farming and forestry. Forest and Bird list scallops as "Worst Choice" in their Best Fish Guide for sustainable seafood species. On the east coast of the United States, over the last 100 years, the populations of bay scallops have greatly diminished due to several factors, but probably is mostly due to reduction in sea grasses (to which bay scallop spat attach) caused by increased coastal development and concomitant nutrient runoff. Another possible factor is reduction of sharks from overfishing. A variety

neg: Common thresher are primarily taken on longlines meant for swordfish and tuna. Common threshers are well regarded by sports fishers as one of the strongest fighting sharks alongside the shortfin mako shark ("Isurus oxyrhinchus"), and are ranked as game fish by the International Game Fish Association. They are pursued by anglers using rod and reel off California, South Africa, and elsewhere. Frank Mundus has called thresher sharks "exceedingly stubborn" and "pound for pound, a harder fish to whip" than the mako. Fishing for the common thresher is similar to that for the mako; the recommended equipment is a rod and a big-game

neg: Live sharksucker Live sharksucker The live sharksucker or slender sharksucker ("Echeneis naucrates") is a species of marine fish in the family Echeneidae, the remoras. The species is considered as circumtropical, as it occurs in all tropical and warm temperate waters around the world, except for the eastern Pacific. The species can be found close to the coast, as well as offshore at a maximum depth of . A live sharksucker is known to attach itself temporarily by its modified dorsal fin used as a sucking disc to various hosts, such as sharks, rays, large bony fishes, sea turtles, whales, dolphins, ships, and

neg: Elizabeth Philpot found in the region. They were able to show him fossils of 34 different species, and he was so impressed by the knowledge of Philpot and Anning that he wrote in his journal: "Miss Philpot and Mary Anning have been able to show me with utter certainty which are the icthyodorulites dorsal fins of sharks that correspond to different types." He thanked both women for their help in his monumental book, "Studies of Fossil Fish", and he named a fossil fish species, "Eugnathus philpotae", after Philpot and another two species after Anning. In 1826 Mary Anning discovered what appeared to

neg: Commercial fishing food chain. This causes a chain effect, leading to an overall upset of the delicate balance of nature. Sharks are one of the ocean's most threatened species because they are mistakenly caught by vessels searching for fish, and end up getting tossed back into the ocean dead or dying This disappearance of sharks has enabled prey animals like rays to multiply, which alters the ecological food chain. "Bycatch" is the industry term for what they consider "unwanted or economically-worthless aquatic animals who are unintentionally caught using destructively indiscriminate fishing methods like longlines and driftnets, which generally target marketable marine creatures