Study on plant speciation in Malesian Archipelago

热带地区具有高度的生物多样性，对物种形成和获得多样性的机制进行研究对于理解热带地区为何能保持如此高的生物多样性是必要的。为此，我们用分子系统发育方法分析了植物的植物地理学。我们于1999年和2000年对印度尼西亚群岛进行了实地考察，2001年对新喀里多尼亚进行了实地考察。我们调查了这些地区的蕨类植物（膜ophylllaceae），裸子植物（Araucariaceae, Podocarpaceae）和被子植物（Nothofagaceae, Anacaradiaceae, Nicotiana）。这些样本被带回日本，我们在cpDNA上测序了matK和rbcL基因，在核基因组上测序了nrDNA的ITS区域。基于这些序列数据，我们用不同的方法重建了系统发生树，并从系统地理学的角度对它们进行了讨论。我们还讨论了基于系统发育树的南半球植物分布演替

Tropical regions have high biodiversity and studies of speciation and mechanism of acquiring diversity are necessary for understanding why they can keep such a high diversity. For this purpose, we analysis phytogeography of the plants using molecular phylogenetic methodology.We have conducted field researches of Indonesian Archipelago in 1999 and 2000, and of New Caledonia in 2001. We investigated ferns (Hymenophyllaceae), Gymnosperms (Araucariaceae, Podocarpaceae), and Angiosperms (Nothofagaceae, Anacaradiaceae, Nicotiana) in these regions. These samples were carried back to Japan and we sequenced matK and rbcL genes on cpDNA, and ITS regions of nrDNA on nuclear genome. Based on these sequence data, we reconstruct phylogenetic trees by various methods, and discussed them from a phylogeographical point of view. We also discussed succession of plant distribution in Southern Hemisphere based on the phylogenetic trees obtained in this study