News
SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It AgainOceanEye to eye with Britain's hidden sharks at SharkAdemy - OceanographicRiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at allOceanShedd Aquarium Sends Shark Eggs to Bolster Wild PopulationsSpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for ConservationOceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray AreaSpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow ReductionsFisheriesAdams River Salmon Run in Thompson-NicolaIndiaHilsa production dropped 26% in five years, fisheries minister tells parliamentSpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It AgainOceanEye to eye with Britain's hidden sharks at SharkAdemy - OceanographicRiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at allOceanShedd Aquarium Sends Shark Eggs to Bolster Wild PopulationsSpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for ConservationOceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray AreaSpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow ReductionsFisheriesAdams River Salmon Run in Thompson-NicolaIndiaHilsa production dropped 26% in five years, fisheries minister tells parliament
EveryFish

Science and research

Model organisms and fish famous in science. 105 fish on EveryFish so far.

Fish are important in science. Some species are model organisms, small, fast-breeding fish that are studied in depth in laboratories to understand biology in general, from how embryos grow to how genes cause disease. Others are famous for what they reveal about evolution, such as the coelacanth, the blind cave fish and the cichlids of the African lakes. Fish also help scientists monitor the health of rivers and seas.

Zebrafish and medaka

The zebrafish, a small striped danio of South Asian streams, became a major model organism from the 1970s and 1980s. Its embryos are see-through and grow outside the mother, so scientists can watch organs and nerves form under the microscope. It is used to study development, heart and nerve disease, cancer and the effects of drugs and pollutants. The Japanese medaka is another model, and in 1994 medaka became the first vertebrates to mate and produce young in orbit, on a Space Shuttle flight.

Fish that explain evolution

The three-spined stickleback has repeatedly lost its bony armour after moving from the sea into lakes, letting scientists trace the genes involved. Sighted and blind forms of the Mexican tetra show how eyes are lost in caves. The turquoise killifish, which lives only a few months, is used to study ageing. The coelacanth and lungfish shed light on how fish first moved onto land, and the spotted gar's genome helps link fish genes to human ones.

Famous science and research fish

ZebrafishA leading model organismJapanese rice fishThe medaka, first vertebrate to breed in orbitMexican tetraSighted and blind formsThree-spined sticklebackA model of evolution in action Turquoise killifishTurquoise killifishThe turquoise killifish, used to study ageingSpotted garIts genome bridges fish and human genesWest Indian Ocean coelacanthA window on the move to land

Still to be written: Guppy.

Further reading

GroupSharkRayCarpCatfishSalmonidHerringCodTunaPerch-likeCichlidReef fishEelFlatfishLivebearerAncientOther
WaterRivers and lakesEstuaries and mangrovesCoasts and shelvesCoral reefsOpen oceanDeep seaPolar and cold seasCaves and springsBetween sea and river
OrderBest knownA to ZOldest firstNewest firstBy size
🇦🇺 Australia and 1 moreAustralian ghostshark A cartilaginous fish native to southern Australia and New Zealand waters.Other · Coasts and shelves WorldBluehead wrasse A small Atlantic reef fish known for changing sex and colour.Other · Coral reefs WorldThree-spined stickleback Small northern fish known for rapid evolution and complex breeding.Other · Rivers and lakes WorldNinespine stickleback Small freshwater fish with variable spines found across the Northern Hemisphere.Other · Rivers and lakes South AsiaGreen spotted puffer Small brackish water pufferfish with a tiny genomeOther · Rivers and lakes WorldWrasse A large family of colourful marine fish known for sex change and cleaning symbiosis.Reef fish · Coasts and shelves WorldPorcupinefish Spiny marine fish that inflate into a defensive sphere to deter predators.Other · Coasts and shelves 🇦🇺 AustraliaCommon seadragon Camouflaged marine fish with leaf-like appendages found in southern Australia.Other · Coasts and shelves 🇺🇸 United StatesSpotted ratfish Cartilaginous fish with a rat-like tail and venomous spineOther · Coasts and shelves

Photo credits on this page

The small pictures above come from Wikimedia Commons under free licences. Some are cropped to fit.

The weekly digest

Every Monday: the fish of the day, new pages on EveryFish, and the conferences and anniversaries of the week ahead.