  We use the latest observations from the 2dF Galaxy Redshift Survey to fit the
conditional luminosity function (CLF) formulation of the halo-model for
galaxies at z=0. This fit is then used to test the extent of evolution in the
halo occupation distribution (HOD) to z=0.8, by comparing the predicted
clustering from this CLF to preliminary results from the DEEP2 Redshift Survey.
We show that the current observations from the DEEP2 Redshift Survey are
remarkably consistent with no evolution in the CLF from z=0 to z=0.8. This
result is surprising, in that it suggests that there has been very little
change in the way galaxies occupy their host dark matter halos over half the
age of the Universe. We discuss in detail the observational constraints we have
adopted and also the various different selection effects in each survey and how
these impact on the galaxy populations encountered in each survey.
