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The Zanzibar red colobus (''Procolobus kirkii'') is a species of red colobus monkey endemic to Unguja, the main island of the Zanzibar Archipelago, off the coast of Tanzania. It is also known as Kirk's red colobus after Sir John Kirk, the British Resident of Zanzibar who first brought it to the attention of zoological science. It is now classified as an endangered species and in the mid-1990s was adopted as the flagship species for conservation in Zanzibar. The population trend is still decreasing, and because this species is only located in the archipelago, conservationists are attempting to work with the local government to devise a proper, effective strategy to protect the population and habitat. The species has been reclassified twice; it was previously in the genus ''Colobus'', and more recently in the genus ''Procolobus''. ==Evolutionary history and taxonomy== The Zanzibar red colobus, ''Procolobus kirkii'', population on Zanzibar, represents a population of red colobus that is believed to have been isolated on the island after sea levels rose toward the end of the Pleistocene epoch. Furthermore, it is suggested through mitochondrial analysis, that phylogenetic groups within the red colobus have been genetically isolated from another since the Pliocene. Examining cranial morphology has shown that ''P. kirkii'' has diverged from mainland ''Procolobus'' to its own species. It has experienced an acceleration in morphological evolution of size which is suggested to be the result of insularity on the island and environmental pressures such as competition, habitat, predation and/or resource availability. There has been no evidence for population bottlenecks in the species.〔 The smaller cranium of ''P. kirkii'' in contrast to the mainland colobus monkey, is consistent with Foster's rule (also known as the island rule) in which the original (larger) animal becomes smaller over time when there is limited resources.〔 Males tend to have pedomorphic traits which include a shorter face, large orbits and an enlarged neurocranium. It is not certain how long ago and where this evolutionary change occurred. Through molecular analyses, it is indicated that ''P. kirkii'' is more closely related to the Udzungwa red colobus (''P. gordonorum'') compared to other red colobus species. This analysis has also placed the divergence of ''P. kirkii'' from its sister species ''P. godronorum'' at about 600,000 years ago, which actually allows for an older evolutionary age compared to the previous assumption that it had become its own species around the last glacial period. The species has been reclassified twice; it was previously in the genus ''Colobus'', and more recently in the genus ''Procolobus''.〔 An alternative common name is Kirk's red colobus after Sir John Kirk (1832–1922), the British Resident of Zanzibar who first brought it to the attention of zoological science.〔(Inventory Acc.942 Papers of Sir John Kirk GCMB KCB and Lady Kirk née Helen Cooke ). National Library of Scotland: Manuscripts Division.〕 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「Zanzibar red colobus」の詳細全文を読む スポンサード リンク
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