A fish is any aquatic An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that live in them can be categorized as aquatic or vertebrate Vertebrates are members of the subphylum Vertebrata, chordates with backbones or spinal columns. About 58,000 species of vertebrates have been described. Vertebrata is the largest subphylum of chordates, and contains many familiar groups of large land animals. Vertebrates comprise cyclostomes, bony fish, sharks and rays, amphibians, reptiles, animal that is typically ectothermic Ectothermic, from the Greek ectos, "outside" and therme, "heat," refers to organisms that control body temperature through external means. As a result, organisms are dependent on environmental heat sources and have relatively low metabolic rates. For example, many reptiles regulate their body temperature by basking in the sun (or cold-blooded), covered with scales In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran (butterfly and moth) species, scales are plates on the surface of the insect wing, and provide coloration. Scales are quite common and have evolved multiple times with varying structure and function, and equipped with two sets of paired fins A fin is a surface used to produce lift and thrust or to steer while traveling in water, air, or other fluid media. The first use of the word was for the limbs of fish, but has been extended to include other animal limbs and man-made devices and several unpaired fins. Fish are abundant in the sea A sea generally refers to a large body of salt water, but the term is used in other contexts as well. Most commonly, the term refers to a large expanse of saline water connected with an ocean, and is commonly used as a synonym for ocean. It is also used sometimes to describe a large saline lake that lacks a natural outlet, such as the Caspian Sea and in fresh water, with species being known from mountain streams (e.g., char Salvelinus is a genus of salmonid fish often called char or charr; some species are called "trout". Salvelinus is a member of the Salmoninae subfamily of the Salmonidae family. Charr may be identified by light cream pink or red spots over a darker body. Scales tend to be small, with 115-200 along the lateral line. Pectoral, pelvic, anal, and gudgeon Gudgeon is a common name for a number of small freshwater fishes of the families Cyprinidae, Eleotridae or Ptereleotridae. Most gudgeons are elongate, bottom-dwelling fish, many of which live in rapids and other fast moving water) as well as in the deepest depths of the ocean An ocean (from Greek Ωκεανός, Okeanos ) is a large body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (an area of some 361,000,000 square kilometres (139,000,000 sq mi)) is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and (e.g., gulpers Saccopharyngiformes is an order of unusual ray-finned fish superficially similar to eels, but with many internal differences. Most of the fish in this order are deep-sea types known from only a handful of specimens such as the Umbrella Mouth Gulper Eel. Saccopharyngiformes are also bioluminescent in several species. Some, such as the swallowers, and anglerfish Anglerfish are the members of the order Lophiiformes . They are bony fish named for their characteristic mode of predation, wherein a fleshy growth from the fish's head (the esca or illicium) acts as a lure; this is considered analogous to angling).
Food prepared from fish is also called fish Fish is a food consumed by many species, including humans. The word "fish" refers to both the animal and to the food prepared from it. Fish has been an important source of protein for humans throughout recorded history, and it is an important food source for humans. They are harvested either from wild fisheries A fishery is an area with an associated fish or aquatic population which is harvested for its commercial value. Fisheries can be marine or freshwater. They can also be wild or farmed. This article is an overview of the habitats occupied by the worlds' wild fisheries, and the human impacts on those habitats (see fishing Fishing is the activity of catching fish. Fish are normally caught in the wild. Techniques for catching fish include hand gathering, spearing, netting, angling and trapping) or farmed Fish farming is the principal form of aquaculture, while other methods may fall under mariculture. Fish farming involves raising fish commercially in tanks or enclosures, usually for food. A facility that releases juvenile fish into the wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish in much the same way as cattle or chickens (see aquaculture Aquaculture is the farming of freshwater and saltwater organisms such as finfish, molluscs, crustaceans and aquatic plants. Also known as aquafarming, aquaculture involves cultivating aquatic populations under controlled conditions, and can be contrasted with commercial fishing, which is the harvesting of wild fish. One half of the world). They are also exploited by recreational fishers Recreational fishing, also called sport fishing, is fishing for pleasure or competition. It can be contrasted with commercial fishing, which is fishing for profit, or subsistence fishing, which is fishing for survival and fishkeepers Fishkeeping is a popular hobby concerned with keeping fish in a home aquarium or garden pond. There is also a fishkeeping industry, as a branch of agriculture, and are exhibited in public aquaria An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants. The term combines the Latin root aqua, meaning water, with the suffix -arium, meaning "a place for relating to&. Fish have had a role in many cultures through the ages, ranging from deities A deity is a postulated preternatural or supernatural immortal being, who may be thought of as holy, divine, or sacred, held in high regard, and respected by believers and religious symbols to the subjects of books and popular movies Film encompasses individual motion pictures, the field of film as an art form, and the motion picture industry. Films are produced by recording images from the world with cameras, or by creating images using animation techniques or visual effects.
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Bloomberg
16 (Bloomberg) -- Diners who'd prefer to skip the salmon may no longer miss out on the fish's omega-3 fatty acids, known to reduce heart disease. ...
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ginoc
hu, 19 Nov 2009 12:59:59 GM
Nice links to various aquatic plant websites. Worth seeing. Nice photography.
