Age–mass relation for red-sequence galaxies in JKCS 041. The clouds of colored points show the probability distribution for each individual galaxy, following the color coding in Fig. 7; ellipses show Laplace approximations. The straight solid line is the mean age–mass relation derived from these posteriors, based on the galaxy spectra and photometry. Fan-shaped lines delineate the error on the mean model (68% highest posterior interval), while the dotted lines indicate the intrinsic scatter (±1σ).