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The bowhead whale (''Balaena mysticetus'') is a species of the right whale family Balaenidae, in suborder Mysticeti, and genus ''Balaena''. A stocky dark-colored whale without a dorsal fin, it can grow to in length. This thick-bodied species can weigh from to . They live entirely in fertile Arctic and sub-Arctic waters, unlike other whales that migrate to low latitude waters to feed or reproduce. The bowhead was also known as the Greenland right whale or Arctic whale. American whalemen called them the steeple-top, polar whale,〔Scammon, Charles M. (1874) (''The Marine Mammals of the North-Western Coast of North America'' ), New York: G.P. Putnam's Sons, ISBN 1597140619.〕 or Russia or Russian whale. The bowhead has the largest mouth of any animal. The bowhead was an early whaling target. The population was severely reduced before a 1966 moratorium was passed to protect the species. Through conservation efforts, the bowhead population has since recovered and is now rated "Least Concern" on the IUCN Red List of Threatened Species.〔 ==Taxonomy== Carl Linnaeus first described this whale in the 10th edition of his ''Systema Naturae'' (1758). Seemingly identical to its cousins in the North Atlantic, North Pacific and Southern Oceans, they were all thought to be a single species, collectively known as the "right whale", and given the binomial name ''Balaena mysticetus''. Today, the bowhead whale occupies a monotypic genus, separate from the right whales, as was proposed by the work of John Edward Gray in 1821.〔 "The taxonomy is not in doubt.... Concerning common names, the species was once commonly known in the North Atlantic and adjacent Arctic as the Greenland Right Whale. However, the common name Bowhead Whale is now generally used for the species."〕 For the next 180 years, the Balaenidae family was the subject of great taxonometric debate. Authorities have repeatedly recategorized the three populations of right whale plus the bowhead whale, as one, two, three or four species, either in a single genus or in two separate genera. Eventually, it was recognized that bowheads and right whales were in fact different, but there was still no strong consensus as to whether they shared a single genus or two. As recently as 1998, Dale Rice, in his comprehensive and otherwise authoritative classification, ''Marine mammals of the world: systematics and distribution'', listed just two species: ''B. glacialis'' (the right whales) and ''B. mysticetus'' (the bowheads). Studies in the 2000s finally provided clear evidence that the ''three'' living right whale species do comprise a phylogenetic lineage, ''distinct from the bowhead'', and that the bowhead and the right whales are rightly classified into two separate genera. The right whales were thus confirmed to be in a separate genus, ''Eubalaena''. The relationship is shown in the cladogram below: |label2= |2= }} }} }} ''Balaena prisca'', one of the five ''Balaena'' fossils from the late Miocene (~10 Mya) to early Pleistocene (~1.5 Mya), may be the same as the modern bowhead whale. The earlier fossil record shows no related cetacean after ''Morenocetus'', found in a South American deposit dating back 23 million years. An unknown species of right whale, the so-called "Swedenborg whale" which was proposed by Emanuel Swedenborg in the 18th century, was once thought to be a North Atlantic right whale by scientific consensus. However based on later DNA analysis those fossil bones claimed to be from "Swedenborg whales" were confirmed to be from bowhead whales.〔(【引用サイトリンク】title=Whale bones found in highway were not from mystery whale )〕 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「bowhead whale」の詳細全文を読む スポンサード リンク
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