The floral evolution of Ericales

这个dfg项目的目标是研究植物目植物的进化。它们的显著特点是花的多样性高，因而缺乏统一的形态特征。因此，寻找共享的衍生（突触）特征是这个项目的目标之一。这些字符的发现不仅会加深我们对埃里卡莱斯的理解，也会加深我们对其最近的相关类群的理解，例如阿斯特拉莱斯。另一个目标是利用现存和灭绝的埃里卡物种的数据重建埃里卡属植物及其亚群的祖先花。这两个目标彼此紧密相连，并将使用最大的形态学和分子数据集进行研究。例如，利用祖先状态重建的结果，我可以推断出颧形花（有一个反射轴的花）是在埃里卡莱系统发育中进化过一次还是多次，以及这是在地球历史上什么时候发生的。所获得的见解将进一步了解埃里卡莱斯的花进化，并有可能揭示适用于所有开花植物的花进化的一般原理。此外，该项目旨在评估“系统扫描”方法的性能，当它用于一个焦点群而不是所有开花植物时，在这个案例中是埃里卡莱斯。“pyhloscan”是一种推断化石在特定类群系统发育中的位置的新方法。在这种多步骤的方法中，化石的所有可能位置都被比较，在每一步中，参考组被缩小。首先是与所有开花植物进行比较，然后是与亚群进行比较，比如菊科植物。目的是将使用“系统扫描”恢复的系统发育位置与目前使用的常规方法进行比较。对于进化生物学家来说，“系统扫描”是一个强大的新工具，因为它消除了手动将化石分配给一个群体时通常涉及的偏见。这是因为每个可能的位置都是通过计算机测试和评分的，所以分数可以比较。总而言之，该项目的目标是利用现存和化石物种的数据重建原始的埃里卡莱斯花。以及使用“系统扫描”方法仔细地将埃里卡化石分配到系统发育中的位置。

The goal of this DFG-project is the study of floral evolution in the plant order Ericales. They are notable for their high floral diversity and the resulting the lack of uniting morphological characters for the order. Therefore, the search for shared derived (synapomorphic) characters is one the goals of this project. The discovery of such characters will deepen our understanding not only of Ericales, but also of its nearest related groups, e.g. Asterales. An additional goal is the reconstruction of the ancestral flower of Ericales and their subgroups using data from living and extinct Ericalean species. Theses two goals are tightly connected with one another and will be studied using the largest morphological and molecular dataset for Ericales, yet. For example, using the results from the ancestral state reconstruction I can infer whether zygomorphic flowers (flowers with one axis of reflection) have evolved once or multiple times within the Ericales phylogeny and when this has been during earth’s history. The insights gained will further the understanding of the floral evolution within Ericales and potentially uncover general principles of floral evolution that stand true for all flowering plants. Furthermore, this project aims to evaluate the performance of the “phyloscan”-method, when it is used for a focal group instead of all flowering plants, in this case Ericales. “pyhloscan” is a new approach to a infer the position of fossils in the phylogeny of a given group. In this multi-step approach all possible positions of a fossils are compared and in each step the reference group is narrowed down. First is always the comparison to all flowering plants and then sub-groups, such as orders like Ericales. The goal is the comparison of the phylogenetic positions recovered using “phyloscan” with those of conventional methods currently used. The “phyloscan” is a powerful new tool for evolutionary biologists because it eliminates the bias usually involved when manually assigning a fossil to a group. That is because each possible position is tested and scored in a computer-based approach, so that scores can be compared. Summarising, the goals of this project are the reconstruction of the ancestral Ericales flower using data from living and fossil species. As well as the careful assignment of Ericalean fossils to positions within the phylogeny using the “phyloscan”-method.