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Darwin's fox or Darwin's Zorro (''Lycalopex fulvipes'') is a small critically endangered canine from the genus ''Lycalopex''. It is also known as the Zorro Chilote or Zorro de Darwin〔 in Spanish and lives on Nahuelbuta National Park, (Araucanía Region), the Valdivian Coastal Range (Los Ríos Region) in mainland Chile and Chiloé Island.〔Farías, A.A., M.A. Sepúlveda, E.A. Silva-Rodríguez, A. Eguren, D. González, N.I. Jordán, E. Ovando, P. Stowhas. 2014. A new population of Darwin’s fox (''Lycalopex fulvipes'') in the Valdivian Coastal Range. ''Revista Chilena de Historia Natural'' 87:3.〕 Darwin's fox was first collected from San Pedro Island off the coast of Chile by the naturalist Charles Darwin in 1834. It was long held that Darwin's fox was a subspecies of the South American gray fox (''L. griseus''); however, the discovery of a small population of Darwin's fox on the mainland in Nahuelbuta National Park in 1990〔Medel, R.G. et al. 1990. Discovery of a continental population of the rare Darwin fox, ''Dusicyon fulvipes'' (Martin, 1839) in Chile. ''Biological Conservation'' 51:71-77〕 and subsequent genetic analysis has clarified the fox's status as a unique species.〔Yahnke, C.J. et al. 1996. Darwin's Fox: A Distinct Endangered Species in a Vanishing Habitat. ''Conservation Biology'' 10:366-375〕 In 2012 and 2013 the presence of the Darwin's fox at Oncol Park, Alerce Costero National Park and the Valdivian Coastal Reserve was confirmed through camera trapping.〔 ==Taxonomy and evolution== ''Pseudalopex'' is a South American genus of canine distantly related to wolves and is technically not a fox. When Charles Darwin collected a specimen from San Pedro Island in Chiloé Archipelago in December 1834 during the ''Beagle'' survey expedition, he observed that this "fox (of Chiloe, a rare animal) sat on the point & was so absorbed in watching (work ), that he allowed me to walk behind him & actually kill him with my geological hammer".〔Keynes, R. D. ed. 2001. ''Charles Darwin's Beagle diary''. Cambridge: Cambridge University Press. pp. (272–273 )〕 In the 1839 publication of his ''Journal and Remarks'', Darwin said "This fox, more curious or more scientific, but less wise, than the generality of his brethren, is now mounted in the museum of the Zoological Society." He said it was "an undescribed species",〔Darwin, C. R. 1839. ''Narrative of the surveying voyages of His Majesty's Ships Adventure and Beagle between the years 1826 and 1836, Journal and Remarks 1832–1836''. London: Henry Colburn. p. ( 341 )〕 indicating that it was distinct from the species (''L. culpaeus'' and ''L. griseus'') that occur on the mainland. Later, Darwin's fox was classified as a subspecies (''Lycalopex griseus fulvipes'') of the latter. Darwin's fox does not interbreed with the other ''Lycalopex'' species, only lives in forests, and is smaller and darker-colored than the other species. In 1990 a small population of Darwin's fox was found on the mainland in the forested Nahuelbuta National Park, indicating that the fox was not endemic to the island. According to Yahnke et al., in their 1996 article published in the Journal of the Society for Conservation Biology, analysis of mitochondrial DNA of Darwin's fox and the gray fox showed two patterns, indicating Darwin's fox was a new species, closely related to the Sechuran fox. Also according to Yahnke (1995; et al.1996) the present restricted range is a relic of a much wider former range. Zoologists noted the distinctiveness in the ecological niche, appearance, and behavior of this species. Darwin's fox is differentiated from the gray fox in being darker; having shorter legs; a broader, shorter skull; smaller auditory bullae; a more robust dentition; and a different jaw shape and style of premolar occlusion. In the late Pleistocene, Chiloé Island was connected to mainland Chile by a land bridge. The land bridge was severed about 15,000 years ago when the sea level rose following the last glaciation.〔Villagrán, C. 1988. Late Quaternary vegetation of Southern Isla Grande de Chiloë, Chile. ''Quaternary Research'' 29: 294–306〕 This created two isolated populations of Darwin's fox. 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「Darwin's fox」の詳細全文を読む スポンサード リンク
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