Ursprung, Speziation, Ausbreitung und intraspezifische Differenzierung arktischer und antarktischer Schlangensterne der Gattung Ophiocten: Hinweise aus vergleichenden Untersuchungen molekulargenetischer Signaturen

脆性恒星（棘皮动物门：蛇尾总科）已被确定为北极和南极海洋底栖生态系统的关键要素。然而，尽管它们具有一般的生态意义，但许多物种在起源、物种形成、分类地位和分布范围方面的信息很少，与生物特征（生命周期和繁殖方式）和地质历史（板块构造和气候振荡）有关。因此，我们提出了一个案例研究的丰富和广泛的属Ophiocten为了调和模式的系统发育关系和最近的地理分布的北极，大西洋和南极物种的剧烈环境变化的过程中进化的时间尺度。将应用分子方法阐明（i）物种和（ii）种群水平的遗传相似性模式：将利用各种分子遗传特征的比较分析（i）推断选定物种之间的系统发育关系，以描述极地海洋的物种形成和定殖过程，并解决密切相关分类群的分类地位问题，以及（ii）跟踪的meroacetonic幼虫的传播路线，并确定遗传上不同的人口。

Brittle stars (Echinodermata: Ophiuroidea) have been identified as key elements of benthic ecosystems in both Arctic and Antarctic seas. However, despite their general ecological significance, there is only scarce information for many species with respect to origin, speciation, taxonomic status and distribution range in relation to biological traits (life cycle and reproduction mode) and geological history (plate tectonics and climate oscillations). Therefore, we propose a case study on the abundant and widespread genus Ophiocten in order to reconcile patterns in phylogenetic relationship and recent biogeographic distribution of Arctic, Atlantic and Antarctic species with the course of drastic environmental changes at evolutionary time scales. Molecular methods will be applied to elucidate genetic similarity patterns at both (i) species and (ii) population level: The comparative analysis of various molecular genetic signatures will be used (i) to deduce the phylogenetic relationships between selected species in order to describe the course of speciation and colonization of polar seas and to solve the taxonomic status of closely related taxa, as well as (ii) to track the dispersal routes of meroplanktonic larvae and to identify genetically distinct populations.