- 著者
- TOMOHITO NAGAOKA AKIO SHIZUSHIMA JUNMEI SAWADA SOICHIRO TOMO KEIGO HOSHINO HANAKO SATO KAZUAKI HIRATA
- 出版者
- The Anthropological Society of Nippon
- 雑誌
- Anthropological Science (ISSN:09187960)
- 巻号頁・発行日
- vol.116, no.2, pp.105-113, 2008 (Released:2008-08-27)
- 参考文献数
- 30
- 被引用文献数
- 27 33
The purpose of this study was to develop new standards for determining the sex of fragmentary human skeletal remains. We measured height, width, and length of the mastoid process in medieval to early modern Japanese skeletons, from the Yuigahama-minami and Hitotsubashi sites, in order to provide a metric standard for the diagnosis of sex using the mastoid process. We calculated discriminant functions based on these measurements; the accuracy of sex classification was over 80% using a single variable, and reached 82–92% with two variables, mastoid height and width. This accuracy is equal to or better than that reported by some previous studies of sex determination using the cranium. However, when we examined intra- and interobserver errors in the mastoid process measurements, we found a high level of errors, and this highlights the difficulty involved in intraobserver repeatability and interobserver reproducibility. Our results imply that, in order to achieve reliable results of sex determination using the mastoid process, the measurement methods need to be carefully determined and executed.
- 著者
- Takashi Yamamoto Hiroyoshi Kohno Akira Mizutani Hanako Sato Hiroki Yamagishi Yutaka Fujii Miku Murakoshi Ken Yoda
- 出版者
- The Ornithological Society of Japan
- 雑誌
- ORNITHOLOGICAL SCIENCE (ISSN:13470558)
- 巻号頁・発行日
- vol.16, no.1, pp.17-22, 2017 (Released:2017-03-01)
- 参考文献数
- 42
- 被引用文献数
- 14
There is increasing evidence showing that wind velocity affects the flight and foraging behavior of seabirds; however, few studies have examined these effects on seabirds inhabiting tropical oceans where lighter wind conditions usually prevail. The Brown Booby Sula leucogaster is an example of a tropical seabird with relatively low wing loading; strong wind conditions may be expected to impede the stability of their flight. We examined how different wind conditions affected the duration and flying behavior of Brown Booby fledglings during foraging trips by means of direct observation of nest attendance and by attaching video loggers to birds. The duration of foraging trips by fledglings decreased with increasing wind speed, and during flight, the body rotation of fledglings became greater with increasing wind speed. As expected, fledglings were buffeted by strong winds due to their relative inexperience in flight combined with their low wing loading. Fledglings were probably forced to flap against strong winds in order to adjust the stability of their bodies, offsetting the efficient use of wind for gliding. Furthermore, the height at which fledglings flew fluctuated more at higher wind velocities, which may have constrained their detection and capture of prey. In conclusion, our results indicate that the aerodynamic performance of Brown Booby fledglings is impaired by strong wind conditions, leading to poor flight stability and potentially reduced prey detection.