Massive starburst galaxies in the early Universe are estimated to havedepletion times of $\sim 100$ Myr and thus be able to convert their gas veryquickly into stars, possibly leading to a rapid quenching of their starformation. For these reasons, they are considered progenitors of massiveearly-type galaxies (ETGs). In this paper, we study two high-$z$ starbursts,AzTEC/C159 ($z\simeq 4.57$) and J1000+0234 ($z\simeq 4.54$), observed with ALMAin the [CII] 158-$\mu$m emission line. These observations reveal two massiveand regularly rotating gaseous discs. A 3D modelling of these discs returnsrotation velocities of about $500$ km/s and gas velocity dispersions as low as$\approx 20$ km/s, leading to very high ratios between regular and randommotion ($V/\sigma {\lower.7ex\hbox{$\;\stackrel{\textstyle>}{\sim}\;$}} 20$),at least in AzTEC/C159. The mass decompositions of the rotation curves showthat both galaxies are highly baryon-dominated with gas masses of $\approx10^{11}M_{\odot}$, which, for J1000+0234, is significantly higher than previousestimates. We show that these high-$z$ galaxies overlap with $z=0$ massive ETGsin the ETG analogue of the stellar-mass Tully-Fisher relation once their gas isconverted into stars. This provides dynamical evidence of the connectionbetween massive high-$z$ starbursts and ETGs, although the transformationmechanism from fast rotating to nearly pressure-supported systems remainsunclear.

We investigate the stellar populations of passive spiral galaxies as afunction of mass and environment, using integral field spectroscopy data fromthe Sydney-AAO Multi-object Integral field spectrograph Galaxy Survey. Oursample consists of $52$ cluster passive spirals and $18$ group/field passivespirals, as well as a set of S0s used as a control sample. The age and [Z/H]estimated by measuring Lick absorption line strength indices both at the centerand within $1R_{\rm e}$ do not show a significant difference between thecluster and the field/group passive spirals. However, the field/group passivespirals with log(M$_\star$/M$_\odot)\gtrsim10.5$ show decreasing [$\alpha$/Fe]along with stellar mass, which is $\sim0.1$ dex smaller than that of thecluster passive spirals. We also compare the stellar populations of passivespirals with S0s. In the clusters, we find that passive spirals show slightlyyounger age and lower [$\alpha$/Fe] than the S0s over the whole mass range. Inthe field/group, stellar populations show a similar trend between passivespirals and S0s. In particular, [$\alpha$/Fe] of the field/group S0s tend to beflattening with increasing mass above log(M$_\star$/M$_\odot)\gtrsim10.5$,similar to the field/group passive spirals. We relate the age and [$\alpha$/Fe]of passive spirals to their mean infall time in phase-space; we find a positivecorrelation, in agreement with the prediction of numerical simulations. Wediscuss the environmental processes that can explain the observed trends. Theresults lead us to conclude that the formation of the passive spirals and theirtransformation into S0s may significantly depend on their environments.

We explore stellar population properties separately in the bulge and the diskof double-component cluster galaxies to shed light on the formation oflenticular galaxies in dense environments. We study eight low-redshift clustersfrom the Sydney-AAO Multi-object Integral field (SAMI) Galaxy Survey, using 2Dphotometric bulge-disk decomposition in the $g$, $r$ and $i$-bands tocharacterize galaxies. For 192 double-component galaxies with$M_{*}>10^{10~}M_{\odot}$ we estimate the color, age and metallicity of thebulge and the disk. The analysis of the $g-i$ colors reveals that bulges areredder than their surrounding disks with a median offset of 0.12$\pm$0.02 mag,consistent with previous results. To measure mass-weighted age and metallicitywe investigate three methods: (i) one based on galaxy stellar mass weights forthe two components, (ii) one based on flux weights and (iii) one based onradial separation. The three methods agree in finding 62% of galaxies havingbulges that are 2-3 times more metal-rich than the disks. Of the remaininggalaxies, 7% have bulges that are more metal-poor than the disks, while for 31%the bulge and disk metallicities are not significantly different. We observe23% of galaxies being characterized by bulges older and 34% by bulges youngerwith respect to the disks. The remaining 43% of galaxies have bulges and diskswith statistically indistinguishable ages. Redder bulges tend to be moremetal-rich than the disks, suggesting that the redder color in bulges is due totheir enhanced metallicity relative to the disks instead of differences instellar population age.