  We present a semi-analytic model of isolated dwarf galaxy evolution and use
it to study the build-up of observed correlations between dwarf galaxy
properties. We analyse the evolution using models with averaged and individual
halo mass assembly histories in order to determine the importance of
stochasticity on the present-day properties of dwarf galaxies. The model has a
few free parameters, but when these are calibrated using the halo mass -
stellar mass and stellar mass-metallicity relations, the results agree with
other observed dwarf galaxy properties remarkably well. Redshift evolution
shows that even isolated galaxies change significantly over the Hubble time and
that 'fossil dwarf galaxies' with properties equivalent to those of
high-redshift analogues should be extremely rare, or non-existent, in the Local
Universe. A break in most galaxy property correlations develops over time, at a
stellar mass $M_* \simeq 10^7 M_\odot$. It is caused predominantly by the
ionizing background radiation and can therefore in principle be used to
constrain the properties of reionization.
