Mass assembly look-back time distributions vs. stellar mass for singlets (empty boxes) and grouped galaxies (filled boxes) in voids (blue), filaments and walls (green) and clusters (red). Upper, middle and lower panels correspond to T₅₀, T₇₀ and T₉₀ distributions, respectively. The stellar mass bins are distributed from 10⁹ to 10¹¹ M_⊙, in 0.5 dex intervals. Numbers at the lower end of each panel correspond to the size of the subsamples (black for singlets and cyan for galaxies in groups).