Data from: Genetic drift and selection in many-allele range expansions

We experimentally and numerically investigate the evolutionary dynamics of
four competing strains of E. coli with differing expansion velocities in
radially expanding colonies. We compare experimental measurements of the
average fraction, correlation functions between strains, and the relative
rates of genetic domain wall annihilations and coalescences to simulations
modeling the population as a one-dimensional ring of annihilating and
coalescing random walkers with deterministic biases due to selection. The
simulations reveal that the evolutionary dynamics can be collapsed onto
master curves governed by three essential parameters: (1) an expansion
length beyond which selection dominates over genetic drift; (2) a
characteristic angular correlation describing the size of genetic domains;
and (3) a dimensionless constant quantifying the interplay between a
colony’s curvature at the frontier and its selection length scale. We
measure these parameters with a new technique that precisely measures
small selective differences between spatially competing strains and show
that our simulations accurately predict the dynamics without additional
fitting. Our results suggest that the random walk model can act as a
useful predictive tool for describing the evolutionary dynamics of range
expansions composed of an arbitrary number of genotypes with different
fitnesses.