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The eastern wolf (''Canis lycaon'', formerly ''Canis lupus lycaon''), also known as the eastern timber wolf, Algonquin wolf or deer wolf〔 〕〔Thiel, R. P. & Wydeven, A. P. (2012). (Eastern Wolf (''Canis lycaon'') Status Assessment Report: Covering East-Central North America ), ''U. S. Fish and Wildlife Service''〕 is a canid native to the northeastern side of North America's Great Lakes region.〔Beeland, T. D. (2013). ''Secret World of Red Wolves: The Fight to Save North America's Other Wolf'', UNC Press Books, ISBN 1469601990〕 It is a medium-sized canid which, like the red wolf, is intermediate in size between the coyote and Northwestern wolf. It primarily preys on white-tailed deer, but may occasionally attack moose and beaver.〔Theberge, J.B. & M.T. Theberge (2004). ''The wolves of Algonquin Park, a 12 Year Ecological Study'', Department of Geography, Publication Series Number 56, University of Waterloo, Waterloo, Ontario〕〔Rutledge, L. Y. (May 2010). ''Evolutionary origins, social structure, and hybridization of the eastern wolf (''Canis lycaon'')'', (), Trent University, Peterborough, Ontario, Canada〕 The eastern wolf's taxonomic identity has been the subject of controversy, with numerous different theories having been presented as to its origin, including that it is a subspecies of gray wolf,〔 that it is conspecific with the red wolf,〔 that it is a result of gray wolf-coyote hybridization, and that it is a unique species.〔 ,〔 the eastern wolf is still recognized as a gray wolf subspecies by MSW3, though was classed as a distinct species by United States Fish and Wildlife Service in 2013 after a comprehensive review of several genetic studies. These studies indicated that the eastern wolf evolved in North America, unlike the gray wolf which originated in Eurasia, and diverged from a common ancestor with the coyote and red wolf 150,000–300,000 years ago.〔 However, in 2014, the research of Chambers et al. (2012) about the eastern wolf's status as a species became controversial, forcing the USF&WS to commission a peer review of it, known as NCAES (2014). This peer review concluded unanimously that the Chambers review "is not accepted as consensus scientific opinion or best available science" and "the issue is not yet settled". Two subsequent reviews of updated research in 2013 and 2014, one commissioned to the Wildlife Management Institute by the USFWS, and one journal review, concluded that historically there were four unique canid species in North America, gray wolf, eastern wolf, coyote and dog, and that "the red wolf may be conspecific with the eastern wolf". This view consistent with the idea that the coyote and gray wolf did not historically range into the eastern United States.〔 These reviews and a 2015 genetics study, the most comprehensive to date,〔 led the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in May, 2015 to change the designation of the eastern wolf to a distinct species, ''Canis lycaon''. However, the previous assertion that gray wolves did not occur in the eastern third of the United States is still ill-founded by the newer genetic study's lead author Dr. Linda Y. Rutledge who noted in the conclusions that "the recognition of the eastern wolf as a separate species does not exclude the possibility that a grey wolf × eastern wolf hybrid animal (previously identified as Canis lupus lycaon, boreal/Ontario-type), similar to a Great Lakes boreal wolf currently located in the Great Lakes states and across Manitoba, northern Ontario, and northern Quebec, historically inhabited the northeastern United States alongside eastern wolves, and there is some evidence to support the historical presence of both Canis types." The eastern wolf is currently listed as a ''Threatened Species'' under COSEWIC and with the Committee on the Status of Species at Risk in Ontario (COSSARO), because "new genetic analyses indicate that the eastern wolf is not a subspecies of grey wolf" versus earlier theories that it was a result of hybridization with both gray wolves and coyotes.〔 The eastern wolf is particularly susceptible to hybridization, due to its close relationship to the coyote and its ability to bridge gene flow between both coyotes and gray wolves. Furthermore, human persecution over a period of 400 years caused a population decline which reduced the number of suitable mates, thus facilitating coyote gene swamping into the eastern wolf population. Aside from posing a threat to a unique species, the resulting eastern wolf-coyote hybrids are too small in size to substitute pure eastern wolves as apex predators of moose and deer. The main nucleus of pure eastern wolves is currently concentrated within Algonquin Provincial Park, south central Ontario and south central Quebec. ==Taxonomic history and evolution== The eastern wolf was first recognized as a distinct species in 1775 by German naturalist Johann Schreber, who termed it ''loup noir'' (black wolf). His depiction of the animal however showed it with a black coat, an atypical coloration in eastern wolves. It was later reclassified as a subspecies of gray wolf by Edward Nelson and Goldman.〔 In 2000, the taxonomic status of the eastern wolf was once again brought into question when a genetic study on canids from Algonquin Provincial Park undertaken in Trent University showed that the local wolves bore similarities to red wolves, based on DNA profiles at eight microsatellite loci. Furthermore, sequences were found in both eastern and red wolves that diverged from those of coyotes by 150,000-300,000 years, and no specimens of either species from the 1960s bore any gray wolf mtDNA. The scientists involved in this study proposed that the eastern and red wolf were the same species, and that the two be combined under the earlier binomial name of ''C. lycaon''. However, this conclusion was disputed, with one study indicating that the eastern wolf is a gray wolf-coyote hybrid〔 and MSW3〔 listed it in 2005 as a subspecies of gray wolf. In May 2011, an analysis of eastern wolf, red wolf, gray wolf, and dog genomes suggested that the wolves of Algonquin Provincial Park are 58% gray wolf and 42% coyote, suggesting that the eastern wolf is a coywolf with more gray wolf content than the red wolf. This study analyzed 48,000 SNP and found no evidence for a unique eastern wolf species. In 2012, re-analysis of the 2011 SNP study argued that the original SNP study suffered from insufficient sampling and noted that gray wolves do not mate with coyotes.〔 Another Y-chromosome genetic study in 2012 also argued that the eastern wolf and red wolf are not hybrids but rather are a distinct species from the gray wolf, although eastern and red wolves do intermix with coyotes. The same authors have argued that the 2011 SNP study finding that eastern wolves are not an independent species is flawed and that historical hunting and culling of wolves, leading to invasion of coyotes into eastern North America, has led to introgression of coyote mitochondrial and nuclear DNA into fragmented, decimated eastern wolf packs.〔 They and other authors have postulated that large populations of eastern and red wolves with intact social/pack structures are less likely to interbreed with coyotes. The controversy over the eastern wolf's species status was the subject of a comprehensive review of the 2011 and 2012 genetics studies, which concluded that there are four separate species of ''Canis'' in North America, the eastern wolf, red wolf, gray wolf and coyote.〔 As of February 2014, an experiment which produced hybrids of coyotes and northwestern gray wolves in captivity using artificial insemination contributed more information to the controversy surrounding the eastern wolf. The six hybrids produced were weighed shortly after birth and were shown to be larger than western coyote pups born around the same time, despite being delivered by a female coyote. However, at six months of age they were weighed again with the two females weighing 17.6 and 21.8 kilograms respectively while the four males were varied between 20.1 to 26.0 kilograms which is close to the average weigh of adult eastern wolves who in turn are around 25 to 30 kilograms. This research suggests that while the eastern wolves are not coywolves, they are still physically similar to such hybrids. Moreover, the FWS review became controversial, forcing the USF&WS to commission a peer review of it, known as NCAES (2014).〔NCEAS (2014). (Review of Proposed Rule Regarding Status of the Wolf Under the Endangered Species Act. ) Nat'l Cent. for Ecol. Anal. & Synth, Univ. Calif., Santa Barbara. Commissioned by USF&WS.〕 This peer review concluded unanimously that the review "is not accepted as consensus scientific opinion or best available science". In 2015, the most comprehensive genetics study, using comprehensive mitochondrial DNA data, Y-chromosome data and genome-wide data from 127,235 SNP, concluded that "the most parsimonious explanation" is that eastern wolves in Algonquin Provincial Park are "a distinct remnant entity of a historical wolf that most likely existed throughout the eastern United States".〔 〕 The taxonomic reference Mammal Species of the World (2005) does not recognize ''Canis lycaon'', however NCBI/Genbank does list it. 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「eastern wolf」の詳細全文を読む スポンサード リンク
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