Whale sharks, the largest fish, give birth to live young and eat only tiny fish, squid, and plankton. Some species, such as the weedy sea dragon, are so bizarre they seem almost unreal. Fish …

Fish are vertebrates (vertebrates have backbones) that live in water. They breathe using special organs called gills.

If you were asked to think of the ugliest creature you can imagine, you might picture the blobfish: a pale pink gelatinous blob with a droopy, downturned mouth and large, sagging nose.

This shark-like fish is a predator. As they grow up, they feast on crustaceans, like prawn, and eventually fish. Sawfish use their rostrums to activate a “ sixth sense ” that detects electric ...

Their schooling behavior is a social adaptation that provides safety in numbers for the fish as they feed on plankton near coral reefs.

2009年2月22日 · With a head like a fighter-plane cockpit, a Pacific barreleye fish shows off its transparent head and barrel-like eyes in the first specimen ever found alive.

Also known as the paiche or the pirarucu, the arapaima is an air-breathing fish that plies the rainforest rivers of South America's Amazon Basin and nearby lakes and swamps.

They range in size from the 1-inch-long dwarf or pygmy puffer to the freshwater giant puffer, which can grow to more than 2 feet in length. They are scaleless fish and usually have rough to spiky ...

An adaptable, intelligent fish . Goldfish are a hardy aquatic species. They can deal with temperature fluctuations, changes in pH, cloudy water, and even low dissolved oxygen levels.

Long, white tusks break the surface of the icy Arctic water. It’s not a waterlogged herd of unicorns—it’s a pod of narwhals! This species of whale is best known for its tusk—a long, …