​​Population structure, information, and growth in randomly fluctuating environments

In order to survive when their environments change, bacteria employ a host of adaptation mechanisms which are under the evolutionary pressure to operate within the statistics of environmental fluctuations. In proportional bet hedging, a well known mechanism that is analytically accessible in the limit of very slow fluctuations, populations can maximize their long term growth by stochastically inducing physiological adaptations at rates proportional to the rate of environmental change. Yet, when environments change randomly in character and duration, this optimum can shift as the population learns the statistics of the fluctuations. In this talk I will show how population structure encodes the information about the history of environmental change and guides population growth. The relationship between population structure, information and growth in fluctuating environments thus constrains the selection of adaptation rates under fluctuations that are sufficiently random.