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东南亚地区东起菲律宾群岛,西至印度次大陆,北及中国中部,南至巽他群岛,涵盖了世界上25个最重要的生物多样性热点地区之中的6个,具有极其重要的全球生物多样性保护的战略意义。该地区复杂的地质地貌和气候历史使其动植物的种类和数量都极为丰富。经典的生物地理分界线华莱士线和克拉地峡将该地区进一步划分出包括部分巽他群岛和马来半岛在内的南部巽他区和北部印度支那区两个生物多样性热点地区。主要基于形态学的生物地理学研究认为巽他区和印度支那区通过马来半岛陆地相连,并且第四纪大部分时间海平面下降形成大陆桥,直到一万年前该地区的众多岛屿仍与大陆连接,促进了哺乳动物的种群迁徙与基因交流,因此物种种群间的差别将很细微。然而近来分子遗传学研究表明,由于其他生态因素制约,哺乳动物的迁移能力可能比以往认为的低,大陆桥的存在并不一定导致迁徙的发生,许多种群的隔离早在200万年前便已形成,并且没有因为后来冰川期海平面降低而恢复种群交流,而距今7.3万年前发生的苏门答腊多巴超级火山爆发也可能进一步影响了物种间和物种内多样性的形成和分化。通过已有的东南亚哺乳动物种群遗传学研究结果,我们认为物种间或种群间的差异主要表现为三个层次:巽他区种群与印度支那区种群间约百万年尺度的分化,巽他区不同岛屿种群间约数十万年尺度的分化,以及发生于晚更新世的分化事件。已有的东南亚种群遗传学研究主要采用线粒体及核基因多位点数据进行分析,而种群基因组学分析则使得获得详尽的种群历史动态成为可能,并使我们可以进一步了解东南亚哺乳动物类群所经历的物种形成过程。
The Southeast Asian region, starting with the Philippine Islands to the east, the Indian subcontinent to the west, and the central part of China to the north, and to the Qeidas Islands to the south, covers 6 of the 25 most important biodiversity hotspots in the world, with extremely important global biodiversity The strategic significance of sexual protection. The complex geological landscape and climate history make the species and abundance of flora and fauna extremely rich. The classic biogeographic demarcation line Wallace Line and the Kala isthmus further divide the area into two biodiversity hotspots areas, including the 巽taktu and Malayan Peninsulas, and the northern Indochina. Morphology-based biogeography studies suggest that the 巽ta and Indochina areas are connected by the Malay Peninsula and that sea level declines most of the Quaternary to form the continental bridge until many islands in the area ten thousand years ago remained Mainland connections promote mammalian population migration and gene exchange, so species diversity will be subtle. However, recent studies on molecular genetics show that due to other ecological factors, the migration capacity of mammals may be lower than previously thought. The existence of the Continental Bridge does not necessarily lead to the occurrence of migration. Quarantine of many populations started as early as two million years ago Formation, and the population exchange was not resumed due to the subsequent decrease in sea level during the glacial period. However, the Sumatra-Dopa super-volcanic eruption that occurred 73,000 years ago may also further affect the formation and differentiation of diversity within and among species. Based on the results of the population genetic studies of mammals in Southeast Asia, we think the differences among species or populations are mainly at three levels: about 1 million-year scale differentiation between populations in 巽taqu and Indochina; Differentiation on the order of hundreds of thousands of years between island populations, and differentiation events occurring in late Pleistocene. Existing Southeast Asian population genetics research mainly uses multi-site data of mitochondrial and nuclear genes for analysis, while population genomics analysis makes it possible to obtain detailed population history and make it possible for us to further understand the experiences of mammalian groups in Southeast Asia Species formation process.