PT - JOURNAL ARTICLE AU - Gokhale, Chaitanya S. AU - Giaimo, Stefano AU - Remigi, Philippe TI - Memory shapes microbial populations AID - 10.1101/2020.11.05.370106 DP - 2020 Jan 01 TA - bioRxiv PG - 2020.11.05.370106 4099 - http://biorxiv.org/content/early/2020/11/05/2020.11.05.370106.short 4100 - http://biorxiv.org/content/early/2020/11/05/2020.11.05.370106.full AB - Correct decision making is fundamental for all living organisms to thrive under environmental changes. The patterns of environmental variation and the quality of available information define the most favourable strategy among multiple options, including sensing and reacting to environmental cues or randomly adopting a phenotypic state. Memory – a phenomenon often associated with, but not restricted to, higher multicellular organisms – can help when temporal correlations exist. How does memory manifest itself in unicellular organisms? Through a combination of deterministic modelling and stochastic simulations, we describe the population-wide fitness consequences of phenotypic memory in microbial populations. Moving beyond binary switching models, our work highlights the need to consider a broader range of switching behaviours when describing microbial adaptive strategies. We show that multiple cellular states capture the empirical observations of lag time distributions, overshoots, and ultimately the phenomenon of phenotypic heterogeneity. We emphasise the implications of our work in understanding antibiotic tolerance, and, in general, survival under fluctuating environments.Competing Interest StatementThe authors have declared no competing interest.