|
| unranked_subordo = Cetacea | unranked_superfamilia = Mysticeti | familia = Balaenopteridae | genus = ''Balaenoptera'' | species = ''B. physalus'' | binomial = ''Balaenoptera physalus'' | binomial_authority = (Linnaeus, 1758) | subdivision_ranks = Subspecies | subdivision = *''B.p.physalus'' *''B.p.quoyi'' | synonyms = *''Balaena boops'' L., 1758 *''Balaenoptera rorqual'' Lacép., 1804 *''Physalis vulgaris'' Fleming, 1828 *''Rorqualus musculus'' F. Cuvier, 1836 *''Pterobalaena communis'' Van Beneden, 1857 | range_map = Cypron-Range Balaenoptera physalus.svg | range_map_caption = Fin whale range }} The fin whale (''Balaenoptera physalus''), also called the finback whale, razorback, or common rorqual, is a marine mammal belonging to the suborder of baleen whales. It is the second largest animal after the blue whale,〔(【引用サイトリンク】title=''Balaenoptera physalus'' Fin Whale )〕 the largest growing to long〔 and weighing nearly .〔Lockyer, C. (1976). Body weights of some species of large whales. ''J. Cons. int. Explor. Mer,'' 36 (3); 259–273.〕 The American naturalist Roy Chapman Andrews called the fin whale "the greyhound of the sea... for its beautiful, slender body is built like a racing yacht and the animal can surpass the speed of the fastest ocean steamship."〔Andrews, Roy Chapman. (1916). ''Whale hunting with gun and camera; a naturalist's account of the modern shore-whaling industry, of whales and their habits, and of hunting experiences in various parts of the world''. New York: D. Appleton and Co., p. 158.〕 The fin whale's body is long and slender, coloured brownish-grey with a paler underside. At least two recognized subspecies exist: the North Atlantic and the Southern Hemisphere. It is found in all the major oceans, from polar to tropical waters. It is absent only from waters close to the ice pack at the poles and relatively small areas of water away from the open ocean. The highest population density occurs in temperate and cool waters. Its food consists of small schooling fish, squid, and crustaceans including copepods and krill. Like all other large whales, the fin whale was heavily hunted during the twentieth century and is an endangered species. Over 725,000 fin whales were reported taken from the Southern Hemisphere between 1905 and 1976, as of 1997 survived by only 38,000.〔 The International Whaling Commission (IWC) issued a moratorium on commercial hunting of this whale,〔(【引用サイトリンク】 Revised Management Scheme )〕 although Iceland and Japan have resumed hunting. The species is also hunted by Greenlanders under the IWC's Aboriginal Subsistence Whaling provisions. Global population estimates range from less than 100,000 to roughly 119,000.〔 ==Taxonomy== The fin whale was first described by Friderich Martens in 1675 and then again by Paul Dudley in 1725. The former description was used as the primary basis of the species ''Balaena physalus'' by Carl Linnaeus in 1758.〔 〕 In 1804, Bernard Germain de Lacépède reclassified the species as ''Balaenoptera rorqual'', based on a specimen that had stranded on Île Sainte-Marguerite (Cannes, France) in 1798. In 1830, Louis Companyo described a specimen that had stranded near Saint-Cyprien, southern France, in 1828 as ''Balaena musculus''. Most later authors followed him in using the specific name ''musculus'', until Frederick W. True (1898) showed that it referred to the blue whale. In 1846, the British taxonomist John Edward Gray described a specimen from the Falkland Islands as ''Balaenoptera australis''. In 1865 the German naturalist Hermann Burmeister described a c. specimen found near Buenos Aires about thirty years earlier as ''Balaenoptera patachonicus''. In 1903, the Romanian scientist Emil Racoviță placed all these designations into ''Balaenoptera physalus''. The word ''physalus'' comes from the Greek word ''physa'', meaning "blows", referring to the prominent blow of the species (as described by Martens (p. 132 ): "They know the ''finn-fish'' by the... vehement blowing and spouting up of the water..."). Fin whales are rorquals, members of the family Balaenopteridae, which also includes the humpback whale, the blue whale, the Bryde's whale, the sei whale and the minke whale. The family diverged from the other baleen whales in the suborder Mysticeti as long ago as the middle Miocene, although it is not known when the members of these families further evolved into their own species. Recent DNA evidence indicates that the fin whale may be more closely related to the humpback whale (''Megaptera novaeangliae'') and in at least one study the gray whale (''Eschrichtius robustus''), two whales in different genera, than it is to members of its own genus, such as the minke whales. If further research confirms this theory, the taxonomy would need revision. As of 2006, there were two named subspecies, each with distinct physical features and vocalizations. The Northern fin whale, ''B. p. physalus'' (Linnaeus 1758) inhabits the North Atlantic and the Southern fin whale, ''B. p. quoyi'' (Fischer 1829) occupies the Southern Ocean. Most experts consider the fin whales of the North Pacific to be a third, as yet unnamed subspecies – this was supported by a 2013 study, which found that the Northern Hemisphere ''B. p. physalus'' was not composed of a single subspecies. The three groups mix at most rarely. Clarke (2004) proposed a "pygmy" subspecies (''B. p. patachonica'', Burmeister, 1865) that is purportedly darker in colour and has black baleen. He based this on a single physically mature female caught in the Antarctic in 1947–48, the smaller average size (a few feet) of sexually and physically mature fin whales caught by the Japanese around 50°S, and smaller, darker sexually immature fin whales caught in the Antarctic which he believed were a "migratory phase" of his proposed subspecies. His proposal is not widely accepted and there is no genetic evidence for their existence.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Fin whale」の詳細全文を読む スポンサード リンク
|