Japan Long-Term Visit: Reproductive Synchronization of Long-Spined Sea Urchins

该奖项将支持加州大学圣克鲁兹分校的John S. Pearse博士与其他教授合作。冲绳琉球大学的山口正志和山中清，以及京都同志社大学的小林直正，从1989年3月开始为期6个月。他们将研究热带印度洋-西太平洋海胆属的两种海胆的发育。为了研究该物种的月配子发生节律及其与月光和潮汐周期的关系，以及这些节律如何影响该物种的生育能力，研究人员将1)测定不同地点该物种的月配子发生节律；2)监测种群以发现产卵事件；3)在人工照明的实验室条件下饲养动物，以模拟月光周期；4)尝试通过蜕变-光合作用培养两种物种的幼虫，如果可能的话，还可以培育杂交后代。这个合作项目将使皮尔斯博士有机会接触到热带浅水动物群中广泛分布和具有重要生态意义的成员在日本的组成部分，并得到在饲养和研究这些物种方面有经验的日本实验室和研究人员的支持。由于这些海胆普遍存在，造成生物侵蚀，并对渔民和游泳者造成滋扰，因此进一步了解它们的繁殖模式可能具有重要的生态影响。

This award will support Dr. John S. Pearse of the University of California, Santa Cruz, to collaborate with Profs. Masashi Yamaguchi and Kiyoshi Yamazato of the University of the Ryukus, Okinawa, and Naomasa Kobayashi, of Doshisha University, Kyoto, for six months beginning in March, 1989. They will study the development of two tropical Indo-West Pacific species of sea urchins of the genus Diadema. In order to study the monthly gametogenic rhythms and how these rhythms are related to moonlight and tidal cycles, and how these rhythms affect fertility of these species, the researchers will 1) determine the monthly gametogenic rhythms of the species at different locations; 2) monitor populations to detect spawning events; 3) maintain animals in artificially illuminated laboratory conditions to simulate moonlight cycles and 4) attempt to rear the larvae of both species and, if possible, hybrids, through metamor- phosis. This cooperative project will provide Dr. Pearse with access to Japanese components of widespread and ecologically important members of the tropical shallow-water fauna, as well as to support from Japanese laboratories and researchers with experience in raising and studying these species. Since these sea urchins are prevalent, cause bioerosion, and create a nuisance for fishermen and swimmers, further understanding of their reproductive patterns may have important ecological effects.