\begin{table}%t3
\caption{\label{tab3}A comparative test of the perturbed disk and the merger remnant hypotheses.}     %\centering
\par
{\scriptsize
\par
\begin{tabular}{lll}
\hline
\hline
Observed property & Best hypothesis & Comments \\
\hline
much redder disk than the bulge         & merger remnant & rapid disk rebuilt is predicted (\citealt{Governato07}): renewed disks are thus star forming and dusty (\citealt{Lotz08b})
\\
bar \& two arms  system    & both & expected for both (see text) \\
misaligned dynamical axis  & merger remnant & in absence of significant outflow, it reveals a system not at equilibrium, difficult to explain except by a merger
\\
average disk velocity dispersion (74 km~s$^{-1}$) & merger remnant & unclear which perturbation other than merging can provide such a hot disk ($\sigma>56$~km~s$^{-1}$) \\
velocity dispersion peak locations & merger remnant & only two minor mergers near the two locations may explain such features in a perturbed disk \\
very high disk star formation density & merger remnant & regulation of star formation between gravitational instabilities and porosity  is expected in rotating disks (e.g. \citealt{Silk97})\\
discrepancy from the Tully Fisher & merger remnant & expected in a merger (e.g. \citealt{Puech07}) and quite unexpected in a perturbed disk (see above)\\
half of the stars with ages lower than 800~Myr & merger remnant & correspond to the merger time-scale  during which these stars are formed\\
\hline
\end{tabular}}
\end{table}