  We investigate the morphological and structural evolutions of disk galaxies
in simulations for a wide range of Toomre's $Q$ parameter. In addition to the
inspection of conventional bar modes, we compute the concentration, asymmetry
and clumpiness (CAS) parameters to enlarge the understanding of the galaxy
evolution. These parameters are widely employed to analyze the light
distribution of the observed galaxies, but the adaptation to numerical
simulations is not much considered. While the bar formation takes place in a
considerable range of $Q$ around $1$, barred galaxies originating from $Q>1$
and $Q<1$ disks yield the CAS values that differ significantly. Disks starting
with $Q<1$ develop clumps due to local gravitational instabilities along with
the bar and these clumps play a central role in enhancing the CAS values. That
process is absent in $Q>1$ counterparts in which the evolution is dominated by
linearly unstable two-armed modes that lead to lower CAS values. Likewise,
unbarred galaxies that are obtainable from disks with $Q$ far below and far
above $1$ exhibit greatly different CAS magnitudes. It turns out that the CAS
parameters can serve as indicators of the initial kinematical state and the
evolution history of a disk of any morphology. In addition, we find an
alternative mechanism of the formation of the lopsided barred galaxy when
$Q\lesssim 1$. Bars that evolve in the midst of the clumps can spontaneously
become lopsided at the end.
