Information AboutFish |
| CATEGORIES ABOUT FISH | |
| fish | |
| fisheries science | |
| seafood | |
| ichthyology | |
| aquatic ecologyfish | |
| fisheries science | |
| seafood | |
| ichthyology | |
| aquatic ecology | |
| vertebrates | |
| aquatic organisms | |
|
Fish are Aquatic Vertebrate s that are Cold-blooded , covered with Scales , and equipped with two sets of paired Fin s and several unpaired fins. Fish are abundant in the sea and in fresh water, with species being known from mountain streams (e.g., Char and Gudgeon ) as well as in the deepest depths of the ocean (e.g., Gulper s and Anglerfish ). at the Georgia Aquarium , seen swimming among other schools of fish]] They are of tremendous importance as Food for people around the world, either collected from the wild (see Fishing ) or farmed in much the same way as cattle or chickens (see Aquaculture ). Fish are also exploited for recreation, through Angling and Fishkeeping , and fish are commonly exhibited in public Aquaria . Fish have an important role in many cultures through the ages, ranging as widely as deities and religious symbols to subjects of books and popular movies. DEFINITION The term "fish" is most precisely used to describe any non- Tetrapod Chordate , i.e., an animal with a backbone that has Gill s throughout life and has limbs, if any, in the shape of fins.1 Unlike groupings such as Bird s or Mammal s, fish are not a single Clade but a Paraphyletic collection of Taxa , including Hagfish es, Lamprey s, Sharks And Rays , Ray-finned Fishes , Coelacanths , and Lungfishes .Helfman G., Collette B., & Facey D.: The Diversity of Fishes, Blackwell Publishing, p 3, 1997, ISBN 0-86542-256-7Tree of life web project - Chordates . A typical fish is Cold-blooded ; has a Streamlined body that allows it to swim rapidly; extracts oxygen from the water using gills or an accessory breathing organ to enable it to breath atmospheric oxygen; has two sets of paired fins, usually one or two (rarely three) dorsal fins, an anal fin, and a tail fin; has jaws; has skin that is usually covered with Scales ; and lays eggs that are fertilized internally or externally. , a close relative of the Seahorse . Their leaf-like appendages enable them to blend in with floating seaweed]] However, to each of these there are exceptions. feed and interact with one another on mudflats and are only underwater when hiding in their burrows.2 The Catfish '' Phreatobius Cisternarum '' lives in underground, Phreatic habitats, and a relative lives in waterlogged Leaf Litter .34 Fish range in size from the 16 m (51 ft) Whale Shark to a 8 mm (just over ΒΌ of an inch) long Stout Infantfish . Many types of Aquatic Animal s commonly referred to as "fish" are not fish in the sense given above; see Fish (disambiguation) . CLASSIFICATION Fish are a containing all fish also contains the Tetrapod s, which are not fish. For this reason, groups such as the "Class Pisces" seen in older reference works are no longer used in formal classifications. Fish are classified into the following major groups:
Some palaeontologists consider that Conodonta are Chordate s, and so regard them as primitive fish. For a fuller treatment of classification, see the Vertebrate article. The various fish groups taken together account for more than half of the known vertebrates. There are almost 28,000 known , Gobiidae , Cichlidae , Characidae , Loricariidae , Balitoridae , Serranidae , Labridae , and Scorpaenidae . On the other hand, about 64 families are Monotypic , containing only one species. It is predicted that the eventual number of total extant species will be at least 32,500.Nelson, J. S.: Fishes of the World, John Wiley & Sons, Inc., p 3, 2006 ISBN 0471250317 FISH ANATOMY See Also: Fish anatomy |
|
|