Coevolutionary Dynamics of Viruses and Microbes

Abstract

This chapter discusses coevolutionary dynamics of viruses and microbes. Virus mutation and host mutations occur rapidly, so much so that new virus and host mutants are expected to arise on timescales similar to those for changes in total population. Host evolution to resistance can lead to virus extinction, but such extinction is not inevitable either in the lab or in the field. A single dominant host and virus type can, via a combination of mutation and selection, diversify into multiple virus and host types that coexist in one community. The interaction of multiple virus and host genotypes has fundamental effects on ecological dynamics. When multiple virus and host genotypes are present, their interactions can lead to novel ecological dynamics, such as apparently reversed predator–prey cycles. Moreover, the interactions of a single virus–host pair can lead to distinct modes of evolutionary dynamics, for example, fluctuating dynamics, arms races, and diversification.