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''Chilotherium'' is an extinct genus of rhinoceros endemic to Eurasia during the Miocene through Pliocene living for 13.7—3.4 mya, existing for approximately . ==Description== It was a large, robust animal reaching 1.5-1.8 m in height and a weight between 1 and 2.5 tons, depending on the species. Both sexes are horn-less. The lower jaw has a widened symphysial part and large tusk-like second incisors separated by a broad diastema. The dental formula is . The limbs are very short and the body stout; the feet are tridactyl with diverging metapodials. Studying ''C. wimani'', found a significant sexual dimorphism in the tusks and mandible, most notably the length of the tusks in males. argued that some features in ''Chilotherium'', such as second incisors, mandible, cheek-teeth and other cranial features, are plesiomorphic, while some features in the tusks are apomorphic: the dorsal surface of the tusks in primitive species is turned latero-dorsally in more derived species while the medial edge has become very sharp and sickle-like and rotated dorsally, and thus a more effective cutting tool. ''Chilotherium'' were a group of grazing animals that radiated into several subgenera and species. Their feet were tridactyl and their legs shorter than in related groups. A few of them remained browsers, but most of them were adapted to a grass-based diet, hence the short legs. Their heads were horn-less but equipped with tusk-like lower incisors and were held in a horizontal position, in contrast to modern rhinos. They inhabited the so-called sub-Paratethyan or Greek-Iranian province during the late Miocene when this region was invaded by advanced rhinos from Africa, such as ''Ceratotherium'' (modern white rhinos). Like them, ''Chilotherium'' gradually evolved into specialised grazers, including hypsodont teeth and shortened metapodials. 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「Chilotherium」の詳細全文を読む スポンサード リンク
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