琉球列島の後期更新世～完新世の脊椎動物
1980 年 18 巻 4 号 p. 263-267
詳細
1980 年 18 巻 4 号 p. 263-267
The mammalian fauna of Okinawa in the period from Late Pleistoceneto Recent is discussed. The Ryukyu Islands are known for abundant occurrence of deer fossils of Miocene type. The Yamashita-cho site of fossil man, 32, 100±1, 000y.B.P. (TK-78) in age, yields deer fossils and no other mammals. On the other hand, at the site of the Minatogawa man, 18, 250±650y.B.P. (TK-99) to 16, 600±300y.B.P. (TK-142) in age, deer fossils become few while boar fossils increase remarkably. This indicates that the Ryukyu boar gained ground taking the place of deer.
Wild boars are living in such islands as Amami Oshima, Okinawa, Ishigaki and Iriomote, and many shell-mounds reveal the existence of boar. In all probability, migration of Sus must have taken place since the time of the Minatogawa man, that is, during the Würm maximum. Geologically the Ryukyu Islands are supposed to have been already separated from the continent at that time, but the occurrence of Sus suggests that the islands were partly connected with the continent even in the Würm maximum.
