Mass-age (top row) and mass-metallicity (bottom row) distributions of galaxies with S/N ≥ 20, colour-coded by the uncertainties δ in mass (left panels), light-weighted mean age (central panels), and light-weighted mean metallicity (right panels) estimates. The green lines identify the number density levels enclosing 16%, 50%, 84%, and 97.5% of the complete galaxy sample. The dotted horizontal lines indicate the solar metallicity of Z_⊙ ≡ 0.02.