Research

Our group focuses* on understanding how populations evolve when they grow and expand on surfaces (in contrast to a well-mixed environment like test tubes).

* More broadly, we are excited about and always up for a chat or project on how the laws of physics facilitate and constrain processes in biology.

Range expansions – why and how we study them

Theoretical work

We use a combination of simulations and analytical description to investigate how structure of the environment (‘landscape structure’) influences the evolutionary fate of an expanding population. As an example, the video below illustrates the effect of a bump encountered by a population front originating from a collaboration. The initially well-mixed population demixes into individual sectors whose fate is then shaped by the curvature of the surface, here, a Gaussian bump. For more details see the recent work on Evolution of populations expanding on curved surfaces published in the Focus Issue Evolutionary modeling and experimental evolution of Europhysics Letters.

Experimental work

We use microbial model systems to study population and evolutionary dynamics in the laboratory. Our favourite model system is bacteriophage T7. The video below shows the spread of bacteriophage T7 on a lawn of E. coli. Bacteria susceptible to phage infection carry a yellow fluorescent marker, bacteria designed (chosen genotype) to be resistant carry a red fluorescent marker. The map of the world was created using a printing technique Wolfram Möbius developed in the context of the publication How Obstacles Perturb Population Fronts and Alter Their Genetic Structure.