  We present the results of N-body simulations of the accretion of high-density
dwarf galaxies by low-density giant galaxies. Both galaxies contain power-law
central density cusps and point masses representing supermassive black holes;
the ratio of galaxy masses is 3:1. The cusp of the dwarf galaxy is always
disrupted during the merger, leading to a remnant with a weak power law in the
intrinsic density and a ``core'' in the projected density. Removing both black
holes from the giant and dwarf galaxies allows the dwarf galaxy to remain
intact and leads to a remnant with a high central density, contrary to what is
observed. Our results support the hypothesis than the persistence of
low-density cores in giant galaxies following mergers is a consequence of the
existence of supermassive central black holes.
