Andreas Wagner Lab

How does nature innovate? How does it create novel adaptations that help organisms survive and reproduce? Darwin taught us how evolutionary innovations can spread. But his theory is silent about their origins. We are interested in principles of evolutionary innovation that go beyond the well-worn notion that novel adaptations require random DNA mutations. To identify such principles, we study three classes of systems. These are macromolecules like proteins and RNA, gene regulatory circuits, and metabolic networks of biochemical reactions. Together, these systems bring forth most or all evolutionary innovations. We use a combination of experimental evolution, comparative genomics, and computational modeling to find out how new traits originate in these systems, and to identify commonalities that lead us to the deeper principles we are seeking.

One central aspect of this research program is the relationship between genotype and phenotype. Between the lower, genetic level of biological organization and the higher level of organisms, a huge gap in our knowledge exists. The reason is that we know so little about how genotypic (DNA) change translates into phenotypic change. One goal of the lab's researchers is to help fill this gap. For example, we use laboratory evolution experiments to study how evolving organisms or molecules evolve new phenotypes while adapting to new environments. We then map such phenotypic changes to genotypic changes through high-throughput sequencing and molecular genetic assays. We also compare regulatory circuits, as well as metabolic networks, and model their evolution. How do these networks form their phenotypes? How did they evolve? How do their phenotypes change in different environments and after mutations? How robust are they to genetic change? How does their robustness affect the ability to create new phenotypes?

Another important research theme revolves around genome architecture, and how it can facilitate or hinder an organism's ability to create new adaptations. For example, most genomes harbor gene duplicates and other kinds of repetitive DNA, such as transposable elements. Do gene duplications merely cause a passive expansion of genome size, are they an engine of innovation, or merely a source of robustness against mutations? Are transposable elements really only parasites inside cells, the ultimate selfish genes, or do they provide benefits to their hosts?

The lab is part of the large and active Zurich research communities in evolutionary biology and computational biology.