Populations, Information, and Entropy
Edo Kussell (Biology, NYU)

Microorganisms have a large and varied repetoire of responses at their disposal to cope with environmental fluctuations. Organisms may employ two general types
of mechanisms to trigger these responses: (1) sensor-based mechanisms, which couple the result of a measurement to an appropriate response, and (2) stochastic switching mechanisms, which maintain a diversity of responses at the population level without direct sensing.  In this talk, a model will be presented that describes
both cases, and identifies conditions that favor each type of mechanism.  Entropy is shown to play two roles in this model: (1) an information-theoretic role, in
which the population's growth rate is seen to depend directly on the amount of information available toorganisms about their environment, and (2) a statistical-mechanical role, which derives from a physical analogy for population growth.