Evolutionary phase transitions in fluctuating environments

by Edo Kussel (New York University)

Friday 27 Jun 2025, 16:00 → 17:00 Europe/Rome

Aula Conversi (Dipartimento di Fisica-Ed. G.Marconi)

Bacteria possess a very large toolbox of molecular mechanisms, coded by specific genes, which enable survival under stressful conditions. These mechanisms on their own are often inefficient or costly, and only by using them strategically do bacteria gain a long-term advantage. This talk examines the strategies that bacteria use to regulate their survival toolbox. By encoding and using memory in different ways, bacteria can optimize their long-term growth potential. This optimization can be understood by a statistical mechanics analogy. I describe a phase diagram structure in which memory levels are optimized as a function of the statistics of a randomly fluctuating environment, and bacterial survival strategies can undergo different types of phase transitions. We are currently studying this phase diagram experimentally, and I will discuss some of our recent experiments quantifying costs and benefits of gene regulation in fluctuating environments.