Authors: Matthew Asker, Mohamed Swailem, Uwe C. Täuber, and Mauro Mobilia
Paper published in Physical Review Research: Phys. Rev. Research 7, 043205:1-28 (2025)
You can find the preprint on arXiv at 10.48550/arXiv.2504.08433 and on bioRxiv at 10.1101/2025.04.10.648186
Supporting code and data can be found here: 10.5518/1660
Lay summary of the paper:
Fluctuating Environments Tip the Balance in Microbial Evolution
Microbes rarely live in steady conditions — nutrients, temperature, and other factors fluctuate unpredictably across space and time. This study shows that these environmental ups and downs, combined with how microbes move in space, can decisively determine whether new mutant strains survive or go extinct. Using mathematical models of many small, interconnected populations exposed to randomly switching “mild” and “harsh” conditions, the authors found that the success of a mutant depends not just on its strength, but on the timing of environmental changes and how quickly the microbes move. In harsh conditions, populations can experience severe bottlenecks, creating a complex interplay between extinction and competition. The study identifies conditions where harmful mutants can be eliminated without endangering the entire population. This work provides a predictive framework for understanding microbial evolution in realistic, changing landscapes — from soil and oceans to the human gut — and offers insights that could guide strategies to control antibiotic resistance and treat cancers.
