We derive deep luminosity functions (to Mz=−15) for galaxies in Abell 1835
(z=0.25) and AC 114 (z=0.31) and compare these with the local z′
luminosity function for 69 clusters. The data show that the faint-end upturn,
the excess of galaxies above a single Schechter function at Mz<−17, does
not exist in the higher redshift clusters. This suggests that the faint-end
upturn galaxies have been created recently, by infall into clusters of
star-forming field populations or via tidal disruption of brighter objects.^MComment: 6 pages, MNRAS main journal, accepted for publicatio