metallicity \[Z/H\] and the mass, [@kol09] do not find any trend involving \[Fe/H\] for Fornax-cluster and nearby-group dEs.

Moreover, from the deconvolution of the SF history of their sample dEs with respect to the central 1 arcmin and within the effective radius [@kol09] draw the conclusions that for a few objects SF episodes occurred in the very center even within the last 1 Gyr. From a systematic study of the central Fornax-cluster dEs’ dynamics [@rij10] conclude that these objects stem from an infall population of late-type DGs and has been transformed to dEs by ram-pressure stripping (RPS).

Toloba et al. [@tolo09] derive for Coma cluster dEs to be weaker in carbon than dEs in low-density environments, while similar in nitrogen. Actually, they [@tol11] also find that pressure supported Virgo dEs show higher dynamical mass-to-light ratios than rotationally supported dEs of similar luminosity and further that dEs in the outer parts of the cluster are mostly rotationally supported with disky shapes. Rotationally supported dEs even follow the Tully-Fisher relation. One fundamental and most spectacular result [@tol11] is, however, that dEs are not DM-dominated galaxies, at least up to the half-light radius.

Correlations of both signatures, SF history and metallicity gradients, for 