Plate tectonics, topographic structures, ocean currents, and mass extinction: How did these factors shape the current distribution of meiofaunal holobenthic Kinorhyncha in deep-sea basins of the Arctic, Atlantic, and Southern Ocean?

大约一半的地球表面被深海所占据，那里有几种独特的生物和生态系统。这种独特性可能是由几个历史事件或地理运动造成的，例如，板块构造洋流和物种大灭绝虽然深海底小型底栖动物的生物量和物种多样性往往高于大型底栖动物，但对它们的分类学、地理学和进化知识却很少进行研究。这里应用的项目是基于小型底栖动物样本的15个德国和4个美国美国深海探险队到北极，大西洋和南大洋。该项目的目标是通过使用小型底栖动物群Kinorhyncha揭示创建当前深海小型底栖动物群落的机制。该研究将全面涵盖上述海洋，并在工作物种一级确定动吻类，从而能够发现它们的地方/区域/海洋特征，并比较盆地内以及盆地与邻近浅水沃茨之间的动物群。有些材料将用于分子系统发育分析，以查明深海动物群和浅水动物群之间的关系。将进行社区结构分析，以比较区域内/区域间社区的相似性。这些动物区系和系统发育比较的结果，加上对该地区历史和地质事件的已知了解，将表明小型底栖动物群落如何在深海海底发展，以及哪些因素影响了它们。该项目的成果将有助于了解深海生物的物种多样性、地理特征和进化历史。

About half of the earth’s surface is occupied by the deep sea where several unique organisms and ecosystem are present. Such an uniqueness may have been created by several historical events or geographical movement, e.g., plate tectonics, ocean currents, and mass extinction. Although meiofauna often shows higher biomass and species diversity than macrofauna in the deep-sea floor, the taxonomical, biogeographical and evolutional knowledge of them has been scarcely investigated. The here applied project is based on meiofauna samples of 15 German and 4 US American deep-sea expeditions to the Arctic, Atlantic, and Southern Ocean. The goal of this project is to reveal the mechanisms which created the current deep-sea meiofaunal community by using the meiofaunal group Kinorhyncha. The study will comprehensively cover the above mentioned oceans and identify the kinorhynchs from there at working species level enabling to detect the local/regional/oceanic characteristics of them and to compare the faunae within basins and between basins and adjacent shallow waters. Some materials will be used for molecular phylogenetic analyses in order to detect the relationships among/between deep-sea faunae and shallow water ones. Community structural analyses will be conducted to compare the (dis)similarities of communities within/between regions. These results of the faunistic and phylogenetic comparisons together with the already known knowledge of the historical and geological events in the area will indicate how meiofaunal community developed on the deep-sea floor and which factors affected them. The results of the project shall contribute to the knowledge on the species diversity, the biogeographical characters, and the evolutional history of deep-sea organisms.