Spatial range expansions with antagonistic interactions

• Applicant: Dr. Jonathan Bauermann
• Subject Area: Statistical Physics, Nonlinear Dynamics, Complex Systems, Soft and Fluid Matter, Biological Physics ; Biophysics
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 523468936

Evolutionary competition determines the spatial range expansion of populations with different species. For example, species with higher reproduction rates can invade new territories more quickly. However, even with identical reproductive rates, stochastic number fluctuations of individuals can lead to the dominant existence of one species and the extinction of others in newly acquired territories. In both cases, initially homogeneous populations separate and form spatial sectors with high genetic similarity. However, direct interactions between individuals of different species can also significantly influence the spatial expansion of populations. For example, previous work has shown that symbiotic interactions lead to the preferential mutual occupation of new habitats. Thus, the population stays homogeneous in space. Furthermore, the static coexistence of immobile species with antagonistic interactions has been studied theoretically and experimentally in colonies of killer yeast cells recently. Here, an effective surface tension resulting from the malicious interactions was described. With the research related to the proposal submitted here, we intend to study the influence of antagonistic interactions on the spatial range expansion of populations of immobile species. First, we want to explore how such interactions alter population expansion dynamics as a whole. In particular, we are interested in how the segregation into spatial sectors and the growth behavior of these sectors depend on the strength of interactions between individuals. Furthermore, we want to investigate the influence of the effective surface tension on the emerging interface between genetic sectors. Here, the interface fluctuations are the main focus of our interest. I want to work with Prof. David R. Nelson (Harvard University) for this research. Furthermore, I plan to collaborate with Prof. David R. Nelson's existing collaboration partners to enable and study these systems' experimental realizations.

• DFG Programme: WBP Fellowship
• International Connection: USA
• Host: Professor David R. Nelson