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| unranked_subordo = Cetacea | unranked_superfamilia = Mysticeti | familia = Balaenidae | genus = ''Eubalaena'' | species = ''E. australis'' | species_authority = (Desmoulins, 1822) | binomial = ''Eubalaena australis'' | range_map = Cypron-Range Eubalaena australis.svg | range_map_caption = Range | synonyms = * ''B. glacialis'' (Mueller, 1776) * ''B. antarctica'' (Lesson, 1828) * ''B. antipodarum'' (Gray, 1843) * ''Hunterus temminckii'' (Gray, 1864) * ''Macleayius australiensis'' (Gray, 1865) * ''E. capensis'' (Gray, 1866) * ''Halibalaena britannica'' (Gray, 1873) * ''E. glacialis australis'' (Tomilin, 1962) * ''B. glacialis australis'' (Scheffer & Rice, 1963) |synonyms_ref= }} The southern right whale (''Eubalaena australis'') is a baleen whale, one of three species classified as right whales belonging to the genus ''Eubalaena''. Like other right whales, the southern right whale is readily distinguished from others by the callosities on its head, a broad back without a dorsal fin, and a long arching mouth that begins above the eye. Its skin is very dark grey or black, occasionally with some white patches on the belly. The right whale's callosities appear white due to large colonies of cyamids (whale lice). It is almost indistinguishable from the closely related North Atlantic and the North Pacific right whales, displaying only minor skull differences. It may have fewer callosities on its head and more on its lower lips than the two northern species.〔 Approximately 10,000 southern right whales are spread throughout the southern part of the Southern Hemisphere. The size of an adult female is 〔Branch, G.M., Branch, M.L, Griffiths, C.L. and Beckley, L.E. 2010. ''Two Oceans: a guide to the marine life of southern Africa'' ISBN 978-1-77007-772-0〕 and can weigh up to ,〔 with the larger records of in length and in weight,〔Department of Sustainability and Environment. 1998. (Southern Right Whale - Eubalaena australis ). Action Statement-Flora and Fauna Guarantee Act 1988. No.94. Retrieved on 31 October. 2014〕 making them slightly smaller than other right whales in Northern Hemisphere.〔Whale and Dolphin Conservation Society. (Endangered Species - SOUTHERN RIGHT WHALE Eubalaena australis ). Retrieved on 31 October. 2014〕 The testicles of right whales are likely to be the largest of any animal, each weighing around . This suggests that sperm competition is important in the mating process. Right whales cannot cross the warm equatorial waters to connect with the other (sub)species and (inter)breed: their thick layers of insulating blubber make it impossible for them to dissipate their internal body heat in tropical waters. However, based on historical records and unconfirmed sightings in modern periods, ''E. australis'' actually do occur in equatorial waters.〔 The proportion and numbers of molten-coloured individuals are notable in this species compared with the other species in the Northern Hemisphere. Some whales remain white even after growing up. ==Taxonomy== The right whales were first classified in the ''Balaena'' genus in 1758 by Carl Linnaeus, who at the time considered all of the right whales (including the bowhead) as a single species. Through the 1800s and 1900s, in fact, the Balaenidae family has been 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. In the early whaling days, they were all thought to be a single species, ''Balaena mysticetus''.〔 The southern right whale was initially described as ''Balaena australis'' by Desmoulins in 1822. Eventually, it was recognized that bowheads and right whales were in fact different, and John Edward Gray proposed the ''Eubalaena'' genus for the right whale in 1864. Later, morphological factors such as differences in the skull shape of northern and southern right whales indicated at least two species of right whale—one in the Northern Hemisphere, the other in the Southern Ocean. As recently as 1998, Rice, in his comprehensive and otherwise authoritative classification, ''Marine mammals of the world: systematics and distribution'', listed just two species: ''Balaena glacialis'' (all of the right whales) and ''Balaena mysticetus'' (the bowheads). In 2000, Rosenbaum et al. disagreed, based on data from their genetic study of DNA samples from each of the whale populations. Genetic evidence now clearly demonstrates that the northern and southern populations of right whale have not interbred for between 3 million and 12 million years, confirming the southern right whale as a distinct species. The northern Pacific and Atlantic populations are also distinct, with the North Pacific right whale being more closely related to the ''southern'' right whale than to the North Atlantic right whale.〔 It is believed that the right whale populations first split because of the joining of North and South America. The rising temperatures at the equator then created a second split, into the northern and southern groups, preventing them from interbreeding.〔(Palaeobiology and Biodiversity Research Group ), University of Bristol〕 In 2002, the Scientific Committee of the International Whaling Commission (IWC) accepted Rosenbaum's findings, and recommended that the ''Eubalaena'' nomenclature be retained for this genus. The cladogram is a tool for visualizing and comparing the evolutionary relationships between taxa. The point where a node branches off is analogous to an evolutionary branching – the diagram can be read left-to-right, much like a timeline. The following cladogram of the Balaenidae family serves to illustrate the current scientific consensus as to the relationships between the southern right whale and the other members of its family. Other junior synonyms for ''E. australis'' have included ''B. antarctica'' (Lesson, 1828), ''B. antipodarum'' (Gray, 1843), ''Hunterus temminckii'' (Gray, 1864), and ''E. glacialis australis'' (Tomilin, 1962) (see side panel for more synonyms).〔〔 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「Southern right whale」の詳細全文を読む スポンサード リンク
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