The floral evolution of Ericales

• Applicant: Dr. Julian Herting
• Subject Area: Evolution and Systematics of Plants and Fungi
• Term: from 2021 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 491286143

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.

• DFG Programme: WBP Fellowship
• International Connection: Australia
• Host: Dr. Hervé Sauquet