  We compare recently measured rest-frame V-band luminosity functions (LFs) of
galaxies at redshifts 2.0<z<3.3 to predictions of semianalytic models by De
Lucia & Blaizot and Bower et al. and hydrodynamic simulations by Dave et al.
The models succeed for some luminosity and redshift ranges and fail for others.
A notable success is that the Bower et al. model provides a good match to the
observed LF at z~3. However, all models predict an increase with time of the
rest-frame V-band luminosity density, whereas the observations show a decrease.
The models also have difficulty matching the observed rest-frame colors of
galaxies. In all models the luminosity density of red galaxies increases
sharply from z~3 to z~2.2, whereas it is approximately constant in the
observations. Conversely, in the models the luminosity density of blue galaxies
is approximately constant, whereas it decreases in the observations. These
discrepancies cannot be entirely remedied by changing the treatment of dust and
suggest that current models do not yet provide an adequate description of
galaxy formation and evolution since z~3.
