The unifying theme of my research is to make a contribution to unravel the Insect Tree of Life as this could provide essential insights into the evolution of global biodiversity, evolutionary processes and key innovations. The importance of insects not only for medical or agricultural issues but also the need to achieve a deep understanding of insect evolution and phylogeny in general has become obvious in the past.
Focusing on the gap of information for several insect orders and to address fundamental questions in evolutionary biology, I have conducted and analyzed transcriptomic projects for five selected key orders (Odonata, Ephemeroptera, Plecoptera, Dermaptera and Zoraptera). These data were used to infer the relationships of the earliest diverging winged insect lineages, the polyneopteran relationships as well as in a grander scheme arthropod relationships. However, uncertainties still exist which might be explained by the missing sequence information for several orders and key taxa. I am participating in the 1KITE project (www.1kite.org) which aims to reconstruct a robust phylogenetic backbone tree of insects by using transcriptomic data of 1,000 insect species.
Comparative transcriptomics of early damselfly development
The new sequencing technologies have massively increased the amount of data available for comparative transcriptomics which can be used to infer insect relationships but also to study the transcriptional signatures and dynamics of developmental processes. However, transcriptomic data across developmental stages are mainly available for derived holometabolous insects, especially drosophilid dipteran species. Therefore, a damselfly a representative of one of the earliest winged insect lineages should be established as non-model system for developmental research and to study in depth the evolution of insect wing development. The new development-dependent transcriptomic information of this non-model organism will help to further study in detail an essential large scale developmental paradigm in developmental biology the molecular signatures of embryonic developmental constraints.
Key mechanistic problems of phylogenetic reconstruction
Nowadays one of the major challenges in phylogenomic studies is not the generation of the data but their analyses and interpretation. This has become one of my research interests and it involves the evaluation of how ortholog prediction, missing data, and taxon and gene sampling contribute to the underlying data quality and consequently the resolution of a certain phylogenetic question. Previous results on this topic have clearly demonstrated that the phylogenomic data matrices harbour a high amount of conflicting phylogenetic signal, which needs to be carefully evaluated; e.g. for some splits within insect evolution the taxon sampling and the function of the genes have a huge impact on the inferred relationships. To address mechanistic problems relevant to phylogenetic reconstruction new workflows will be set including already developed tools as well as various new bioinformatic tools.
Using insect transcriptomic data sets, I am amongst others interested in finding a specific set of genes, based on their biological function and/or interaction, which contain congruent phylogenetic signal and might resolve a specific phylogenetic question. Using this approach the underlying scheme of gene evolution in correlation to species evolution should be elucidated. The difficulty inherent in insect systematics and the competing hypotheses offers in my opinion a great opportunity to explore more detailed while despite the increase of sequence information based on whole genome or transcriptome projects there is still a source of incongruence in the comprehensive data sets. For these purposes especially the growing wealth of data derived from large-scale sequencing efforts will be promising and the outcome of these studies will be highly valuable for systematic studies also for other organisms.