15 0 0 0 OA 瑞浪層群宿洞層(岐阜県瑞浪市釜戸町)よりパレオパラドキシア科の全身骨格の発見
1 0 0 0 OA 北海道,忠類産ナウマンゾウの再検討
The Churui specimen was found in 1969 and 1970 from Bansei, Churui, Makubetus-cho, Nakagawa-gun, Hokkaido, and is one of the most important whole skeletons of Palaeoloxodon naumanni. Herein, we reexamine the molar number and specific identification of this specimen. As a result of our observations, four molars that were previously identified as second molars of one individual are re-identified as third molars of one individual. These molars correspond to the group 25-27 of Laws (1966), and are therefore assumed to represent an age of about 50 years. Observations of the epiphyseal fusion of the postcranial bones in the Churui specimen support the result that the animal used its third molars. A molar that was previously identified as a third molar from the same individual as the four "second molars" of P. naummmni, is re-identified as a second or third molar of the woolly mammoth Mammuthus primigenius, as determined by morphological characters. It gave a radiocarbon date of 42,850+510BP. Woolly mammoths inhabited Hokkaido from 45ka to 16ka, while the horizon of P. naumanni from Churui is estimated to be 120ka. This suggests that the molar of the woolly mammoth fell from the upper part of the cliff at the excavation site of the Churui specimen, instead of being recovered from the excavation plane.
- 著者
- 北川 博道 高橋 啓一
- 出版者
- 化石研究会
- 雑誌
- 化石研究会会誌 (ISSN:03871924)
- 巻号頁・発行日
- vol.43, no.1, pp.30-39, 2010-08
1 0 0 0 IR 瀬戸内海西部諸島周辺海底から産出したナウマンゾウ化石
- 著者
- 北川 博道 瀬戸 浩二 高橋 啓一
- 出版者
- 島根大学
- 雑誌
- 島根大学地球資源環境学研究報告 (ISSN:13439774)
- 巻号頁・発行日
- vol.25, pp.31-47, 2006-12-27
In this paper, we describe 75 tusks and post-cranial skeletal elements of Palaeoloxodon naumanni that were recovered from the sea floor around Moroshima Island in the western Seto Inland Sea of Japan in 1956 and 1957, and discuss their significance.13;These specimens are particularly valuable from the biogeographic and morphological viewpoints due to their locality and the details of their discovery. A sacrum(MO 560929-1126)recovered among these specimens is the first report of a sacrum of P. naumanni. An atlas(MO 560929-1117)and a humerus(MO 57-1112)are also compared with those of previously reported well-preserved specimens of P. naumanni. Although the features of the humerus are comparable with those of P. naumanni humeri reported from other areas, the atlas differs from a Lake Nojiri specimen. The differences between the two specimens are most likely attributable to intraspecific variation.