首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Correlations between feeding type and mandibular morphology in the sika deer
Authors:M Ozaki  G Suwa  K Kaji  T Ohba  E Hosoi  T Koizumi  & S Takatsuki
Institution:Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, Japan;
The University Museum, The University of Tokyo, Bunkyo-ku, Tokyo, Japan;
Hokkaido Institute of Environmental Sciences, Kita-ku, Sapporo, Japan;
Nature Conservation Office, Shizuoka Prefectural Government, Aoi-ku, Shizuoka, Japan;
Department of Biological and Environmental Sciences, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan;
Wildlife Ecology Laboratory, Forestry and Forest Products Research Institute, Tsukuba, Ibaraki, Japan
Abstract:Morphological comparisons of the sika deer Cervus nippon mandible and molars were conducted between two (northern and southern) Japanese subspecific lineages and among local populations of different ('grazer' or 'intermediate feeder') feeding types. The northern lineage showed greater M1 breadth, M3 hypsodonty and mandibular corpus height than the southern lineage. Such differences were not observed between the 'grazer' and 'intermediate feeder' populations of the northern lineage. However, a northern population, which inhabits a particularly harsh environment (Kinkazan Island), had the largest values of relative molar size and hypsodonty, although this was not statistically significant. These results imply that, in the Japanese sika deer, the selective pressures acting on the current 'grazer' populations are not strong enough to bring out noticeable adaptive change in molar size and hypsodonty, but adaptive change in these traits may occur in an environment that promotes excessive molar wear, more than that seen in the current sika deer habitats of Japan. Combined with what is known of the Pleistocene history of the sika deer, we infer that the ancestral population of the northern Japanese lineage likely acquired their relatively larger and more hypsodont molars in an extremely harsh environment during the last or previous glacial periods.
Keywords:cervids  dietary adaptation  microevolutionary levels  molar durability  morphometry
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号