  The formation and evolution of massive red galaxies form a crucial test of
theories of galaxy formation based on hierarchical assembly. In this letter we
use observations of the clustering of luminous red galaxies from the Bootes
field and N-body simulations to argue that about 1/3 of the most luminous
satellite galaxies appear to undergo merging or disruption within massive halos
between z~0.9 and z~0.5.
