  Different evolutionary models are known to make disparate predictions for the
success of an invading mutant in some situations. For example, some
evolutionary mechanics lead to amplification of selection in structured
populations, while others suppress it. Here, we use computer simulations to
study evolutionary populations moved by flows, and show how the speed of this
motion impacts the fixation probability of an invading mutant. Flows of
different speeds interpolate between evolutionary dynamics on fixed
heterogeneous graphs and in well-stirred populations. We find that the motion
has an active role in amplifying or suppressing selection, accomplished by
fragmenting and reconnecting the interaction graph. While increasing flow
speeds suppress selection for most evolutionary models, we identify
characteristic responses to flow for the different update rules we test. We
suggest these responses as a potential aid for choosing the most suitable
update rule for a given biological system.
