We follow the dynamical and chemical evolution of isolated systems tuned in their properties on selfgravitating spherical three component (gas+stars+dark matter) dwarf spheroidal galaxies (dSph). The system starts as a strongly dark matter dominated cuspy density profile. It is shown that after few Gyr of evolution the star formation processes are naturally able to reshape the cuspy dark matter profile into a flatter one. The same family of models is then evolved by orbiting in a Milky Way external potential in order to investigate the history of the Carina dwarf galaxy. Structural parameters and the star formation history of Carina are self-consistently determined in good agreement with the observations.

We use N-body simulations to follow the evolution of bars in the presence of a central mass concentration (CMC). We find that the bar amplitude decreases in response to the CMC, but the bar is not totally destroyed unless the CMC mass is several percent of that of the disc. More centrally concentrated CMCs are more efficient. The bar evolution does not stop after the CMC has fully grown, but continues well after that time.