Speaker
Silvio Franz
(IPTMS)
Description
Several pathogens use evolvability as a survival strategy
against acquired immunity of the host. Despite their high
variability in time, some of them exhibit quite low
variability within the population at any given time, a
somehow paradoxical behavior often called the evolving
quasispecies. In this paper we introduce a simplified model
of an evolving viral population in which the effects of the
acquired immunity of the host are represented by the
decrease of the fitness of the corresponding viral strains,
depending on the frequency of the strain in the viral
population. The model exhibits evolving quasispecies
behavior in a certain range of its parameters, and suggests
how punctuated evolution can be induced by a simple feedback
mechanism.
