Spectral stacks as a function of redshift for objects classified as galaxy in cluster. Top panel: stack of active galaxies in clusters and bottom panel: stack of passive galaxies in clusters. The bottom panel is accompanied by the stack of passive galaxies in clusters from the SPIDERS-CLUSTER observations with their evolution as a function of cluster-centric radius, see Clerc et al. (in prep.) for full details. Vertical displacement between spectra are added for clarity.