1982 Volume 36 Issue 4 Pages 214-218
Kumaishi-do Cave, which is situated at Hachiman-cho, Gifu Prefecture, Central Japan (Long., 137° E; Lat., 35°45'N), is one of the largest limestone caves in this district. The fissure sediments which expose near the entrance of the cave, yield abundant mammalian fossils of the Latest Pleistocene. The fossil assemblage contains 28 forms of mammals. The total ratio of the extinct and exotic forms attains about 50% in large mammals, but only 11% in micro-mammals. It is interesting that the boreal forms such as Alces alces (LINNAEUS) and Ursus arctos LINNAEUS are associated with the temperate forms such as Selenarctos thibetanus (G. CUVIER), Macaco, fuscata (BLYTH) and Sinomegaceros yabei (SHIKAMA). In micro-mammals, it is characteristic that most forms are extant, but the forms which are now distributed sporadically in high mountains are predominant in insectivore assemblage, and extinct and exotic forms such as Microtus epiratticeps YOUNG and Clethrionomys sp. are rarely found. The fossil bones which are obtained from the lower part of the fossiliferous sediments are dated as 16720 ± 880 y. B. P. by 14C method. The age is assigned to the coldest phase of the Wiirm Glacial time in Japan, so it is consistent with the fact that the boreal elements are contained in the assemblage. The occurrences of Palaeoloxodon naumanni (MAKIYAMA), Alces alces, Cervus praenipponicus SHIKAMA, Microtus epiratticeps and Clethrionomys sp. from Kumaishi-do Cave are one of the youngest records in Japan. It is considered that the mammalian fauna of Japan dramatically changed from ca. 16000 to 10000 y. B. P. Many large mammals were extinguished as the climate became warmer since 16000 y. B. P. On the other hand, most of micro-mammals survived to the recent. These facts probably indicate that the large mammals severely suffered the effects of the isolation of the Japanese Islands from the continent and the hunting activities of men.
