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The red wolf (''Canis rufus''/''Canis lupus rufus''〔), also known as the Florida wolf or Mississippi Valley wolf〔Glover, A. (1942), (''Extinct and vanishing mammals of the western hemisphere, with the marine species of all the oceans'' ), American Committee for International Wild Life Protection, pp. 229-233.〕 is a canid of unresolved taxonomic identity native to the eastern United States.〔 It is generally, morphologically, an intermediate between the coyote and gray wolf, and is of a reddish, tawny color.〔〔 Red wolves were likely the first New World wolf species encountered by European colonists and were originally distributed throughout the eastern United States from the Atlantic Ocean to central Texas, and in the north from the Ohio River Valley, northern Pennsylvania and southern New York south to the Gulf of Mexico. The red wolf was nearly driven to extinction by the mid-1900s due to aggressive predator control programs, habitat destruction and extensive hybridization with coyotes. By the late 1960s, it occurred in small numbers in the Gulf Coast of western Louisiana and eastern Texas. Fourteen of these survivors were selected to be the founders of a captively bred population, which was established in the Point Defiance Zoo & Aquarium between 1974 and 1980. After a successful experimental relocation to Bulls Island off the coast of South Carolina in 1978, the red wolf was declared Extinct in the Wild in 1980 in order to proceed with restoration efforts. In 1987, the captive animals were released into North Carolina's Alligator River National Wildlife Refuge, with a second release taking place two years later in the Great Smoky Mountains National Park. The red wolf's taxonomic status has been a subject of controversy. A 2011 genetic study indicated that it may be a hybrid species between gray wolves and coyotes.〔 Re-analysis of this study coupled with a broader contextual analysis including behavioral, morphological and additional genetic information led to arguments that the red wolf is an independent species but has suffered from significant introgression of coyote genes likely due to decimation of red wolf packs with fragmentation of their social structure from hunting. A comprehensive review in October 2012 concluded that the red wolf is a distinct species which diverged from the coyote alongside the closely related eastern wolf 150,000-300,000 years ago,〔 Although this 2012 review was not universally accepted among relevant authorities,〔 two subsequent reviews of updated research in 2013 and 2014 suggest that the red wolf was once a species distinct from the gray wolf and coyote.〔 Finally, a 2015 genetics study, using the most comprehensive mitochondrial DNA data, Y-chromosome data and genome-wide 127,235 SNP data, 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".〔 〕 This view is supported by the idea that the coyote and gray wolf did not historically range into the eastern United States, with current academic debate on red wolf taxonomy shifting to a new question: whether the eastern wolf and red wolf are conspecific,〔 a possibility considered by some researchers.〔 ==Taxonomy== The taxonomic reference Mammal Species of the World (2005) does not recognize ''Canis rufus'', however NCBI/Genbank does list it. The taxonomy of the red wolf has been debated since before efforts began in 1973 to save it from extinction. In 1971, Atkins and Dillon conducted a study on the brains of canids and confirmed the basal characteristics of the red wolf. Many studies throughout the 1970s focused on the morphology of the red wolf came to the conclusion that the red wolf is a distinct species. In 1980, a unique allele was found in ''Canis'' specimens from within the red wolf range, supporting the conclusion that the red wolf is a distinct species. Nevertheless, some in the scientific community considered it a subspecies of the gray wolf〔Lawrence,B. and W. Bossert. 1975. Relationships of North American ''Canis'' shown by a multiple character analysis of selected populations. P. 73-86 in M.W. Fox, ed., ''The wild canids: Their systematic, behavioral ecology, and evolution.'' Van Nostrand Reinhold, New York.〕 or a hybrid of the gray wolf and the coyote.〔Mech, L.1970. ''The wolf: The ecology and behavior of an endangered species.'' Natural History Press, Garden City, NY.〕 In 1992, the USFWS conducted an exhaustive review of the literature, including their own, and concluded that the red wolf is either a separate species unto itself or a subspecies of the gray wolf.〔Nowak et al. (1995). Another look at wolf taxonomy. pp 375–397 In L.N. Carbyn, S.H. Fritts, and D.R. Seip, eds. ''Ecology and conservation of wolves in a changing world''. Canadian Circumpolar Institute, Edmonton, Alberta.〕 Many agency reports, books and web pages list the red wolf as ''Canis rufus'' but genetic research re-opened the debate about the taxonomy of both the red wolf and Canada's eastern wolf (''Canis lupus lycaon''). Wilson et al. (2000) concluded that the eastern wolf and red wolf should be considered as sister taxa due to a shared common ancestor going back 150,000–300,000 years. In addition, Wilson et al. further stated that they should be recognized as distinct species from other North American canids, and not as subspecies of the gray wolf (''Canis lupus''). However, these conclusions were disputed,〔 and ''MSW3'' listed them both in 2005 as subspecies of the gray wolf. In May 2011, an analysis of red wolf, Eastern wolf, gray wolf, and dog genomes suggested that the red wolf was 76–80 percent coyote and only 20–24 percent gray wolf, suggesting that the red wolf is actually much more coyote in origin than the Eastern wolf. This study analyzed 48,000 SNP and found no evidence for a unique Eastern wolf or red wolf species. However, X-Ray analysis of the 16 red wolf specimens used in the SNP study were later shown to be wolf-coyote hybrids via cranial morphometric analysis, rendering the finding that the red wolf was a gray wolf-coyote hybrid inaccurate. The U.S. Fish and Wildlife Service (USFWS) still considers the red wolf a valid species (''Canis rufus'') and plans to make no changes to its recovery program.〔(【引用サイトリンク】publisher=USFWS )〕 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 red 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 red wolf's species status was the subject of a comprehensive review of the 2011 and 2012 genetics studies, which concluded that there are three separate species of wolf in North America, the red wolf, eastern wolf and gray wolf.〔 In a pair of 2012 reports, scientists critical of the May 2011 paper outlined three main points of criticism.〔〔 First, the 2011 paper relied on mtDNA SNPs derived from boxer and poodle genomes and used these to extrapolate inference about genetic variation within wild canids across the globe. While it is true that many SNPs were examined, it remains unclear whether loci important to red wolf genetic variation were actually identified and analyzed (for example, nuclear DNA was not compared in the SNP analysis). Second, the study sampled modern red wolf specimens, and not historic red wolf specimens from prior to 1900 (when extensive hybridization with coyotes is known to have taken place), which obfuscates the reliability of the study's findings. This is important because using historic red wolf genetic material would have created a baseline genetic profile for the species against which to test the modern captive-bred specimens. (It is common knowledge that the captive-bred red wolves are likely slightly hybridized, but this is a separate issue from interpreting their species origin as due to hybridization.) Third, the authors lumped Eastern wolf specimens (which critics from Trent University warn are of unverified origin) with other Great Lakes wolf specimens, and did not test them separately, which again obfuscated any genetic differences that may have been present. The controversy over the eastern wolf's origins is not considered by the scientific community to be laid to rest, although it may be synonymous with the red wolf.〔 When considered as a full species, three subspecies of red wolf were originally recognized by Goldman; two of these subspecies are extinct. The Florida black wolf (''Canis rufus floridanus'') (Maine to Florida) has been extinct since 1930 and Gregory's wolf (''Canis rufus gregoryi'') (south-central United States)〔 was declared functionally extinct in the wild by 1980. The Texas red wolf (''Canis rufus rufus''), the third surviving subspecies, was also functionally extinct in the wild by 1980, although that status was changed to "critically endangered" when captive-bred red wolves from Texas were reintroduced in eastern North Carolina in 1987. The current status of the "non-essential/experimental" population in North Carolina is "endangered" and the population numbers around 100 wild animals.〔(【引用サイトリンク】publisher=U.S. Fish and Wildlife Program )〕 The subspecies designations are essentially moot since two are extinct but the genetic evidence for the three subspecies appears to have been unconvincing anyway.〔 In 2013, 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's taxonomy. The purpose of this project was to determine whether or not if the female western coyotes are capable of bearing hybrid western gray wolf-coyote pups as well as to test the hybrid theory surrounding the origin of the eastern and red wolves by comparing them to both. The resulting six hybrids produced in this captive artificial breeding were later on transferred to the Wildlife Science Center of Forest Lake in Minnesota where their behaviors are now being studied.〔http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0088861〕 While this research is still ongoing, the debate over the eastern wolf's taxonomy remained unsettled. Moreover, in 2014, the review of Chambers et al. (2012) which suggested the eastern wolf should be listed either as a distinct species closely related to the red wolves or conspecific with the latter became controversial, forcing the USFWS to commission a peer review of it, known as NCAES (2014), which took issue with the review.〔Dumbacher, J., (Review of Proposed Rule Regarding Status of the Wolf Under the Endangered Species Act ), NCEAS (January 2014)〕 However, more recent reviews suggest the evidence has "tilted towards a North American canid assemblage composed of the eastern wolf, red wolf and coyote as distinct taxa...that descended from a common ancestral canid of North American origin" before arrival of the gray wolf from Eurasia.〔〔 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「Red wolf」の詳細全文を読む スポンサード リンク
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