We show that a 2+1 dimensional discrete surface growth model exhibiting
Kardar-Parisi-Zhang (KPZ) class scaling can be mapped onto a two dimensional
conserved lattice gas model of directed dimers. In case of KPZ height
anisotropy the dimers follow driven diffusive motion. We confirm by numerical
simulations that the scaling exponents of the dimer model are in agreement with
those of the 2+1 dimensional KPZ class. This opens up the possibility of
analyzing growth models via reaction-diffusion models, which allow much more
efficient computer simulations.Comment: 5 pages, 4 figures, final form to appear in PR