Data from: Rate of novel host invasion affects adaptability of evolving RNA virus lineages

Although differing rates of environmental turnover should be consequential
for the dynamics of adaptive change, this idea has been rarely examined
outside of theory. In particular, the importance of RNA viruses in disease
emergence warrants experiments testing how differing rates of novel host
invasion may impact the ability of viruses to adaptively shift onto a
novel host. To test whether the rate of environmental turnover influences
adaptation, we experimentally evolved 144 Sindbis virus lineages in
replicated tissue-culture environments, which transitioned from being
dominated by a permissive host cell type to a novel host cell type. The
rate at which the novel host ‘invaded’ the environment varied by
treatment. The fitness (growth rate) of evolved virus populations was
measured on each host type, and molecular substitutions were mapped via
whole genome consensus sequencing. Results showed that virus populations
more consistently reached high fitness levels on the novel host when the
novel host ‘invaded’ the environment more gradually, and gradual invasion
resulted in less variable genomic outcomes. Moreover, virus populations
that experienced a rapid shift onto the novel host converged upon
different genotypes than populations that experienced a gradual shift onto
the novel host, suggesting a strong effect of historical contingency.