Studying the diverse nature of faint galaxies in nearby clusters of the WINGS sample

We present the first results of our X-shooter observations for a sample of dwarf (-17 <M_B <-15) galaxies in nearby (0.04 < z < 0.07) galaxy clusters. This luminosity range is fundamental to trace the evolution of higher-z star-forming cluster galaxies down to the present day, and to explore the galaxy scaling relations of early-type galaxies over a broad mass range. Thanks to high resolution and availability of several lines we can derive the velocity dispersion of the galaxies in this range of luminosities and we begin the construction of the fundamental plane of faint early-type galaxies.