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The King Island emu (''Dromaius novaehollandiae minor'') is an extinct subspecies of emu that was endemic to King Island, which is situated in the Bass Strait between mainland Australia and Tasmania. Its closest relative may be the extinct Tasmanian emu (''D. n. diemenensis''), as they belonged to a single population until less than 14,000 years ago, when Tasmania and King Island were still connected. The small size of the King Island emu may be an example of insular dwarfism. The King Island emu was the smallest of all emus, and had darker plumage than the mainland emu. It was black and brown, and had naked blue skin on the neck, and its chicks were striped like those on the mainland. The subspecies was distinct from the likewise diminutive Kangaroo Island emu (''D. baudinianus'') in a number of osteological details, including size. The behaviour of the King Island emu probably did not differ much from that of the mainland emu. The birds gathered in flocks to forage and during breeding time. They fed on berries, grass and seaweed. They ran swiftly, and could defend themselves by kicking. The nest was shallow, and consisted of dead leaves and moss. Seven to nine eggs were laid, which were incubated by both parents. Europeans discovered the King Island emu in 1802 during early expeditions to the island, and most of what is known about the bird in life comes from an interview French naturalist François Péron conducted with a sealer there, as well as depictions by artist Charles Alexandre Lesueur. They had arrived on King Island in 1802 with Nicolas Baudin's expedition, and in 1804 several live and stuffed King and Kangaroo Island emus were sent to France. The two live King Island specimens were kept in the Jardin des Plantes, and the remains of these and the other birds are scattered throughout various museums in Europe today. The logbooks of the expedition did not specify from which island each captured bird originated, or even that they were taxonomically distinct, so their status remained unclear until more than a century later. Hunting pressure and fires started by early settlers on King Island likely drove the wild population to extinction by 1805. The two captive specimens in Paris both died in 1822 and are believed to have been the last of their kind. ==Taxonomy== There was long confusion regarding the taxonomic status and geographic origin of the small island emu taxa from King Island and Kangaroo Island, since specimens of both populations were transported to France as part of the same French expedition to Australia in the early 1800s. The logbooks of the expedition failed to clearly state where and when the small emu individuals were collected, and this has resulted in a plethora of scientific names subsequently being coined for either bird, many on questionable grounds, and the idea that all specimens had originated from Kangaroo Island. Furthermore, in 1914, L. Brasil argued the expedition did not encounter emus on King Island, because the weather had been too bad for them to leave their camp. The French also referred to both emus and cassowaries as "casoars" at the time, which has led to further confusion.〔 Louis Jean Pierre Vieillot coined the binomial ''Dromaius ater'' in 1817. In 1906, Walter Baldwin Spencer coined the name ''Dromaius minor'' based on some Pleistocene subfossil bones and eggshells found on King Island the same year, believing they were the first physical evidence of an emu from there. William Vincent Legge also coined a name for these remains, ''Dromaius bassi'', but at a later date. In his 1907 book ''Extinct Birds'', Walter Rothschild stated that Vieillot's description actually referred to the mainland emu, and that the name ''D. ater'' was therefore invalid. Believing the skin in Muséum national d'Histoire naturelle of Paris was from Kangaroo Island, he made it the type specimen of his new species ''Dromaius peroni'', named after the French naturalist François Péron, who is the main source of information about the bird in life.〔 The Australian amateur ornithologist Gregory Mathews coined further names in the early 1910s, including a new genus name, ''Peronista'', as he believed the King and Kangaroo Island birds were generically distinct from the mainland emu. Later writers claimed that the subfossil remains found on King and Kangaroo Islands were not discernibly different, and that they therefore belonged to the same taxon.〔 In 1959, the French ornithologist Christian Jouanin proposed that none of the skins were actually from Kangaroo Island, after inspecting expedition and museum documents. In 1990, Jouanin and Jean-Christophe Balouet used environmental forensics to demonstrate that the mounted skin in Paris came from King Island, and that at least one live bird had been brought from each island. All scientific names given to the Kangaroo Island emu were therefore based on specimens from King Island or were otherwise invalid, leaving it nameless. More recent finds of subfossil material and subsequent studies on King and Kangaroo Island emu, notably by Shane A. Parker in 1984, confirmed their separate geographic origin and distinct morphology. Parker named the Kangaroo Island bird ''Dromaius baudinianus'', after Nicolas Baudin, the leader of the French expedition. The name ''Dromaius ater'' was kept for the King Island emu. There are few morphological differences that distinguish the extinct insular emus from the mainland emu besides their size, but all three taxa were most often considered distinct species. A 2011 genetic study of nuclear and mitochondrial DNA, which was extracted from five subfossil King Island emu bones, showed that its genetic variation fell within that of the extant mainland emus. It was therefore interpreted as conspecific with the emus of the Australian mainland, and was reclassified as a subspecies of ''Dromaius novaehollandiae'', ''D. n. ater''. Other animals present on King Island are also considered as subspecies of their mainland or Tasmanian counterparts rather than distinct species. The authors suggested that further studies using different methods might be able to find features that distinguish the taxa.〔 In its 2013 edition, The Howard and Moore Complete Checklist of the Birds of the World emended the trinomial name of the King Island emu to ''D. n. minor'', based on Spencer's ''D. minor'', on the ground that Vieillot's ''D. ater'' was originally meant for the mainland emu.〔 〕 This rationale was accepted by the IOC World Bird List, which used ''D. n. minor'' thereafter. 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「King Island emu」の詳細全文を読む スポンサード リンク
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