Comparative Molecular Phylogenetic Study on Speciation and Genetic Differentiation of Marine Organisms between the Pacific Ocean and the Japan Sea

为了揭示更新世大规模环境变化对日本海海洋生物的影响，采用分子系统学方法对日本海各种海洋生物的种群结构进行了分析，并对日本海最具优势的深海底栖鱼类--荷兰槽纹鲷（Bothricara hollandi）进行了分析。表明，该物种的种群由两个遗传上不同的群体组成，并建议没有发生剧烈的环境变化日本圆螺（Turbo（Batillus）cornutus）种群的遗传结构是在更新世形成的，但它的进化周期很短，至今仍保持着清晰的遗传结构;而一种具有更长进化周期的潮间带腹足类Omphalinus pfeifferi种群的遗传结构则是在末次冰期结束后形成的。从日本海分离到的奥氏泥螺（O.pfeifferi）个体在较短的时间内演化为奥氏泥螺（O.pfeifferi carpenteri），而直接发育的泥滩螺（Batillaria cumingi）的遗传结构比同属的多形巴氏泥螺（B.multiformis）和日本头巾螺（Japanese turban shell）的遗传结构更趋分化。日本海和太平洋浅水腹足类中的一些种类，如：Sulculus diversicolor、Astralium haematragum、Chlorostoma argyrostoma和Monodonta labio，没有发现明显的遗传分化。

In order to reveal effects of large enviromnental changes during the Pleistocene on marine organisms in the Japan Sea, population structures of various marine organisms were analyzed using molecular phylogenetic methods.The analysis of the most dominant deep-sea demersal fish of the Japan Sea, Bothricara hollandi, showed that populations of this species consist of the two genetically different groups and it was suggested that no drastic environmental change occurred near the Thushima Strait during the last glacial period.While the clear genetic structure of a population of the Japanese turban shell, Turbo (Batillus) cornutus, whose planktonic period is very short, formed during the Pleistocene and have been kept until now, the genetic structure of an intetidal gastropod wth much longer planktonic period, Omphalinus pfeifferi, was shown to have formed after the end of the last glacial period. Individuals of O.pfeifferi, which were isolated in the Japan Sea, are thought to have become the subspedes, O.pfeifferi carpenteri, in the relatively short period.A direct-developing mud flat snail, Batillaria cumingi, showed more diverged genetic structure than the congeneric planktonic species, B.multiformis as well as the Japanese turban shell. No clear genetic differentiation was detected between the Japan Sea and the Pacific for some shallow water gastropods, namely Sulculus diversicolor, Astralium haematragum, Chlorostoma argyrostoma and Monodonta labio.The present results suggest the importance of larval dispersal ability far the formation of the genetic structures of marine species.