Fish

With an estimated 20,000 different species, there is an immense variety of fish. The variation in size is enormous: the tiny Paedocypris progenetica is only 8 millimetres long, and the whale shark can reach over 12 metres. Fish are adapted to live in many different habitats: trout and catfish can live in freshwater; seahorses and yellow tang fish live in coral reefs; and down on the deep, dark ocean floor are anglerfish and cookie cutter sharks.

The mysterious sex life of eels: How scientists finally unveiled their (truly bizarre) life cycle

Long, silvery and mysterious, these endangered fish make a big journey to reproduce.
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What is a sheepshead fish?

The sheepshead fish has human-like teeth helps it consume an omnivorous diet.
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Blobfish: Facts about the world's ugliest animal

Learn what the blobfish really looks like – and why it’s become an unlikely poster child for marine conservation.
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Why do animals migrate?

Many animals make long, treacherous journeys year after year, so why do they go to all that effort?
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What is a wolf eel?

This voracious eater is not actually an eel...
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What’s the environmental impact of cigarette butts?

Cigarette butts contain chemicals toxic to wildlife and create 845,000 tons of litter every year.
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Ugly fish are under threat of extinction and need saving

Fish that we deem unattractive are often more ecologically important, researchers say, but their prettier relatives are getting more conservation support.
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12 of the weirdest deep-sea creatures that lurk in the oceans' depths

A huge amount of the deep sea is still unknown to us. Take a look at some of the bizarre animals that live down there...
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Scientists taught a goldfish to drive a car, and the research could one day help astronauts in space

And yes, there's a video.
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Octopuses: 8 incredible photos of these magnificent cephalopods

Take a deep dive into the diverse world of some of the most intelligent invertebrates on planet Earth.
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What is a sarcastic fringehead?

No, not something you call your mate when they've been scathing about your outfit, but a big-mouthed, purple-tongued, lip-wrestling, territorial fish.
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Mysteries of the deep sea: 5 burning questions about Earth's final frontier

Will we ever live in a deep-sea base? And how many unknown creatures lurk in the depths?
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Early humans in Israel used modern fishing tools 12,000 years ago

The people who used these tools "knew all there was to know about fish".
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Goblin shark: The nightmarish fish that launches its jaws at its prey

The stuff of nightmares… an aquatic ninja with a pair of extendable jaws and nail-like teeth which sneaks up on its prey by sensing their electrical fields. Lucky you’re not a fish.
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Young great white sharks use ‘training grounds’ to learn to hunt

Researchers say their work could help prevent the species from becoming extinct.
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Why do some animals need more than two eyes?

Asked by: Fatima, Manchester
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