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''Amebelodon'' is a member of a diverse group of primitive proboscideans called gomphotheres, a group that also gave rise to the modern elephants and their close relative the mammoth. The most striking attribute of this animal is its lower tusks, which are narrow, elongated, and distinctly flattened with the degree of flattening varying among the different species. ==Taxonomy== ''Amebelodon'' first appeared in the Great Plains and Gulf Coast regions of North America during the late Miocene, roughly 9 million years ago, and apparently became extinct on this continent sometime around 6 million years ago. It managed to migrate to Asia via the Bering land bridge where it has been found in a number of late Miocene sites, particularly in China. The youngest record of ''Amebelodon'' is from a 5-million-year-old site in North Africa.〔 Lambert, W. D., 1990. Rediagnosis of the genus ''Amebelodon'' (Mammalia, Proboscidea, Gomphotheriidae) with a new subgenus and species, ''Amebelodon'' (''Konobelodon'') ''britti''. Journal of Paleontology, 64 (6): 1032-1041.〕〔 Lambert, W. D., 1996. The biogeography of the Gomphotheriidae of North America. In Tassy, P. and J. Shoshani (eds.), The Proboscidea: Trends in Evolution and Paleoecology. Oxford University Press: Oxford, UK.〕〔Lambert, W. D., and J. Shoshani, 1998. The Proboscidea. In Janis, C., K. M. Scott, and L. Jacobs (eds.), Evolution of Tertiary Mammals of North America, Volume 1. Cambridge University Press: Cambridge, UK.〕 The species ''Amebelodon floridanus'' was relatively small, a little smaller than living elephants, and was common in fossil sites from 9 to 8 million years ago. Other larger but somewhat younger common North American species include ''Amebelodon fricki'' and ''Amebelodon britti''〔 Note that one lineage of large ''Amebelodon'' species, including ''Amebelodon britti'' and North African ''Amebelodon cyrenaicus'', has recently been placed into a new genus called ''Konobelodon'', formerly considered to be a subgenus.〔Konidaris, G. E., S. J. Roussiakis, G. E. Theodorou, and G. D. Koufos. 2014. The Eurasian occurrence of the shovel-tusker Konobelodon (Mammalia, Proboscidea) as illuminated by its presence in the late Miocene of Pikermi (Greece). Journal of Vertebrate Paleontology 34:1437–53.〕 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「Amebelodon」の詳細全文を読む スポンサード リンク
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