Evolution and development of head morphology in closely related Drosophila species

Development

We apply unbiased, genome-wide expression profiling methods (RNAseq) during Drosophila head development to identify core components of the gene regulatory network (GRN) underlying adult head formation (see Fig. A for a simplified network). Developmental genetics and molecular biology approaches are subsequently used to analyze the function of identified key genes during head development.

Evolution

Head size and shape varies between closely related Drosophila species (Posnien et al., 2012). First, we want to reveal the nodes within the head developmental GRN that change in the course of evolution to result in natural variation in head morphology. Second, we want to understand how the evolving genes are integrated in the GRN and how they influence the development of adult head size and shape. We combine genomics, quantitative genetics, geometric morphometrics and developmental genetics approaches to these questions.

In order to find out if the same morphological changes observed in nature are the result of the same molecular changes, we study the evolution of head morphology in three closely related species of the D. melanogaster group (Fig. B) and in two species of the D. virilis group.