  New automated and high-throughput methods allow the manipulation and
selection of numerous bacterial populations. In this manuscript we are
interested in the neutral diversity patterns that emerge from such a setup in
which many bacterial populations are grown in parallel serial transfers, in
some cases with population-wide extinction and splitting events. We model
bacterial growth by a birth-death process and use the theory of coalescent
point processes. We show that there is a dilution factor that optimises the
expected amount of neutral diversity for a given amount of cycles, and study
the power law behaviour of the mutation frequency spectrum for different
experimental regimes. We also explore how neutral variation diverges between
two recently split populations by establishing a new formula for the expected
number of shared and private mutations. Finally, we show the interest of such a
setup to select a phenotype of interest that requires multiple mutations.
