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The Sri Lankan elephant (''Elephas maximus maximus'') is one of three recognized subspecies of the Asian elephant, and native to Sri Lanka. Since 1986, ''Elephas maximus'' has been listed as endangered by IUCN as the population has declined by at least 50% over the last three generations, estimated to be 60–75 years. The species is pre-eminently threatened by habitat loss, degradation and fragmentation. ''Elephas maximus maximus'' is the type subspecies of the Asian elephant, first described by Carl Linnaeus under the binominal ''Elephas maximus'' in 1758.〔Linnaei, C. (1760) (''Elephas maximus'' ) In: ''Caroli Linnæi Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis''. Tomus I. Halae Magdeburgicae. Page 33〕 The Sri Lankan elephant population is now largely restricted to the dry zone in the north, east and southeast of Sri Lanka. Elephants are present in Udawalawe National Park, Yala National Park, Lunugamvehera National Park, Wilpattu National Park and Minneriya National Park but also live outside protected areas. It is estimated that Sri Lanka has the highest density of elephants in Asia. Human-elephant conflict is increasing due to conversion of elephant habitat to settlements and permanent cultivation.〔Fernando, P., Jayewardene, J. Prasad, T., Hendavitharana, W. Pastorini, J. (2011). (''Current Status of Asian Elephants in Sri Lanka'' ). Gajah 35: 93–103.〕 == Characteristics == In general, Asian elephants are smaller than African elephants and have the highest body point on the head. The tip of their trunk has one finger-like process. Their back is convex or level. Females are usually smaller than males, and have short or no tusks.〔Shoshani, J., Eisenberg, J.F. (1982) (''Elephas maximus'' ). Mammalian Species 182: 1–8〕 Sri Lankan elephants are the largest subspecies reaching a shoulder height of between , weigh between , and have 19 pairs of ribs. Their skin color is darker than of ''indicus'' and of ''sumatranus'' with larger and more distinct patches of depigmentation on ears, face, trunk and belly.〔Shoshani, J. (2006) (''Taxonomy, Classification, and Evolution of Elephants'' ) In: Fowler, M. E., Mikota, S. K. (eds.) Biology, medicine, and surgery of elephants. Wiley-Blackwell. ISBN 0813806763. Pp. 3–14〕 Only 7% of males bear tusks.〔Jayewardene, J. (1994). ''The elephant in Sri Lanka''. Wildlife Heritage Trust of Sri Lanka, Colombo〕 According to the elephant census conducted in 2011 by the Wildlife Conservation Department of Sri Lanka, only 2% of the total population are tuskers. Sri Lankan elephants are somewhat diminutive when compared with historical accounts dating back to 200 BC and with photographs taken in the 19th century during the time of colonial British rule of the island. The smaller size could possibly be the end result of a long-continued process of removing the physically best specimens from the potential breeding-stock through hunting or domestication (see insular dwarfism). 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「Sri Lankan elephant」の詳細全文を読む スポンサード リンク
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