Research

We are an international group of evolutionary biologists. Together, we investigate how populations evolve and adapt. The two main themes in the lab are currently 1) the genetic and phenotypic responses of populations to life in poor quality or complex environments, and 2) the role of hybridization in evolution.

Our main model system is the microbe Baker’s yeast (aka Brewer’s or budding yeast – Saccharomyces cerevisiae) and its wild relatives. We use a combination of experimental evolution and genome sequencing to understand what drives the dynamics of adaptation. We work with populations that range in genetic variation from clonal (i.e. genetically identical individuals) to extremely diverse (e.g. hybrid swarms made from crossing different species). We also collect yeast directly from the wild, often from the bark of ancient oak trees, to find out where and how yeast lives! Thanks to the Awesome Power of Yeast Genetics, and the fact that yeast reproduces quickly (asexually and sexually), yeast is great to study what constrains and drives adaptive evolution, and to pin down the contributions of the four population genetic processes – mutation, drift, recombination and selection.

Some of the questions we are currently working on:

• What is the genetic architecture of adaptive traits in different environments?
• How do the type and rate of environmental change affect adaptation dynamics?
• How likely is parallel evolution when populations adapt from standing genetic variation?
• How do structural genomic variants (e.g. aneuploidy) affect fitness?
• Is the distribution of fitness effects (DFE) comparable across environments and systems? This is a collaboration with great colleagues at the Math Dept (Chun-Biu Li).
• We’re also working with insects (at least computationally)! Together with David Berger at Uppsala University, we are looking at parallelism of temperature adaptation in experimental evolution lines of seed beetles (Callosobruchus maculatus).

If you are interested in any of the above or related questions, please contact rike.stelkens@zoologi.su.se

We are always looking for interested Master’s students, who want to join the lab. We are happy to discuss your own interesting project ideas!

Just looking for fun on this page? Check out this awesome yeast rap by Loke von Schmalensee! Sound on!

Illustration by Susanne Landis: www.scienstration.com
Lovely yeasty doodle by Javier Pinto