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Deinotheriidae ("terrible beasts") is a family of prehistoric elephant-like proboscideans that lived during the Cenozoic era, first appearing in Africa, then spreading across southern Asia (Indo-Pakistan) and Europe. During that time they changed very little, apart from growing much larger in size; by the late Miocene they had become the largest land animals of their time. Their most distinctive feature was the downward curving tusks on the lower jaw. Deinotheres were not very diverse; there are only three known genera: ''Chilgatherium'', ''Prodeinotherium'' and ''Deinotherium''. These form an evolutionary succession with each new genus replacing the preceding one. Unlike the various mammoth and mastodont lineages, the deinotheres died out in the early Pleistocene, rather than continuing through the ice age. ==Description== The body shape and proportions of deinotheres were very much like those of modern elephants. The legs were long, like modern elephants, but the skull was rather flatter than that of true elephants. The upper jaw lacked incisor and canine teeth, but possessed five low-crowned molars on each side, with the same number in the lower jaw. Research has shown that deinotheres used their front teeth for crushing their food, and the back teeth for shearing (slicing), the plant material. The front part of the lower jaw was turned downwards, and bore the two tusk-like incisors. These curved downwards and backwards in a sort of huge hook, and constituted the most distinct feature of the deinotheres. The tusks were used to strip vegetation rather than for digging.〔 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「Deinotheriidae」の詳細全文を読む スポンサード リンク
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