Studies on mass speciation in response to major climatic events in the Cenozoic

基于线粒体12s和16s rRNA基因和细胞色素b基因的核苷酸序列数据，对陆生和海洋哺乳动物（鹿科、牛科、水蛭科、水豚科、鲸目、鳖目）、拟鱼目、腹足类海洋腹足类动物（蚓目、蝶目、蟾目）进行了分子系统发育分析。我们的系统发育分析表明，在陆地和海洋生态系统中，许多动物类群的物种形成事件是同步发生的，表明这种大规模物种形成事件是由新生代主要气候事件引起的。本文还提出了日本新近纪和第四纪浅海温水软体动物区系与太平洋新近纪暖海洋气候事件的时间和地理分布的新格局。本研究揭示了暖流事件期间许多暖水物种从南方入侵到中纬度地区，在气候最佳期后它们在日本列岛周围的定居和地理隔离导致了物种的大规模形成。暖流事件不断更新着区系组成，最终形成了预设日黑潮区系。本文总结了日本新近纪和第四纪海洋软体动物的范围图，以清楚地说明大规模物种形成事件的事实。在国际科学期刊和教科书上发表了鲸科、鲸目和准骨类的分子系统发育分析论文。

Molecular phylogenetic analyses were made for a number of animal groups including terrestrial and marine mammals (Cervidae, Bovidae, Suidae, Sirenians, Cetacea, Pinnipedians), euteleostean Perciforms and marine gastropods (Umboniinae, Turbiniidae, Potamididae, Batillariidae and Buccinidae), based on the nucleotide sequence data of mitochondrial 12s and 16s rRNA genes and cytochrome b gene.Our phylogenetic analyses revealed that speciation events occurred synchronously among a number of animal group in both terrestrial and marine ecosystems, suggesting that this mass- speciation events were induced by the major climatic events in the Cenozoic.In this study, a new schema on the chlonological and geographical distribution of the Japanese Neogene and Quaternary shallow marine warm-water molluscan faunas is also presented in relation to the Neogene warmmarine climatic events in the Pacific.The present study revealed that many warm-water species invaded from the south into the mid-latitudes during the warm events and their settlements and geographical isolation around the Japanese Islands after the climatic optima led to mass-speciation. The warm events repeatedly made renewal of the faunal composition and finally have established the preset-day Kuroshio fauna. In this study we summarized the range charts of the Neogene and Quaternary marine molluscs in Japan to show clearly the facts of mass-speciation events. Papers on the molecular phylogenetic analysis of the Cervidae, Cetaceans and euteleostean Perciforms were published on the international scientific journals and text-book.