Evolutionary and Population Dynamics of Bacteria and Phage
- Date: 04/26/2007
Joshua Weitz (Georgia Institute of Technology)
University of British Columbia
Bacterial viruses, aka bacteriophage or phage, are ubiquitous in
nature, yet many central aspects of host-phage biology have not been
integrated into mathematical models. In this talk I present a series of
theoretical efforts to understand the diversity, population dynamics
and life history of phage. First, I discuss an evolutionary ecology
model of host-phage diversification using the framework of adaptive
dynamics and show how the principle of competition exclusion is
modified in the context of coevolutionary arms races. Second, current
models of host-phage population dynamics neglect to include the
reduction of lytic effectiveness as hosts approach stationary phase.
Incorporating reduced lysis into dynamics leads to a prediction of
alternative stable states, which are discussed in the context of simple
experiments. Finally, I explore ongoing experimental and theoretical
efforts to understand how phage may optimally exploit their hosts by
utilizing a variety of life history strategies.
MITACS Math Biology Seminar 2007