We study the evolution of two fundamental properties of galaxy clusters: the luminosity function (LF) and the scaling relations between the total galaxy number N (or luminosity) and cluster mass M. Using a sample of 27 clusters (0<z<0.9) with new near-IR observations and mass estimates derived from X-ray temperatures, in conjunction with data from the literature, we construct the largest sample for such studies to date. The evolution of the characteristic luminosity of the LF can be described by a passively evolving population formed in a single burst at z=1.5-2. Under the assumption that the mass-temperature relation evolves self-similarly, and after the passive evolution is accounted for, the N-M scaling shows no signs of evolution out to z=0.9. Our data provide direct constraints on halo occupation distribution models, and suggest that the way galaxies populate cluster-scale dark matter halos has not changed in the past 7 Gyr, in line with previous investigations.
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