Peixe

Peixes Da Wikipedia, a enciclopédia livre.

Um peixe é um animal vertebrado poiquilotérmico aquático com guelras. Os peixes (mais de 27.315 espécies catalogadas) são divididos em peixes ósseos (classe Osteichthyes, com 22.000 espécies); peixes cartilaginosos (classe Chondrichthyes, 800 espécies); e vários grupos de peixes sem mandíbulas (75 espécies), incluindo as lampréias e os "hagfish". Outros animais aquáticos , taais como as medusas e água-vivas (e os "cuttlefish"), não são verdadeiramente peixes.

Fishes can be found in most all large bodies of water in either salt and fresh water, at depths ranging from just below the surface to several thousand meters. However, hyper-saline lakes like the Great Salt Lake do not support fish.

Some species of fish have been specially bred to be kept and displayed in an aquarium.

Fish are an important source of food. Other water-dwelling animals such as mollusks and crustaceans (commonly called shellfish) are often considered as fish when used as food.

Catching fish for the purpose of food or sport is known as fishing. The annual yield from all fisheries worldwide is about 100 million tonnes.

Above: Atlantic herring Clupea harengus - one of the most abundant species in the world

Above: Black seabass Centropristis striata (photo: Uwe Kils)

Overfishing is a threat to many species of fish. On May 15, 2003, the journal Nature reported that all large oceanic fish species worldwide had been so systematically overcaught that fewer than 10% of 1950 levels remained. [1] Particularly imperilled were sharks, Atlantic cod, and Pacific sardines. The authors recommended immediate, drastic cutbacks in fish catches and reservation of ocean habitats worldwide.

See also: freshwater aquarium fish species, deep sea fishes, halibut, List of fish families, fish farming

External links

A World of Fish [The most complete aquarium site on the internet] Fish database (FishBase) Project for children - build a fish mobile with a behavior