Comparison of the stellar-mass–size relations in field and MACS1206 cluster environments for star forming (blue) and quiescent (red) galaxies and their errorbars. We divide the sample into mass bins for a more detailed description of the sizes. The solid lines show the weighted mean sizes in 0.5 dex mass bins of both samples. The shaded regions indicate the 1σ error on the mean. The red and blue triangles are median points for field galaxies from van der Wel et al. (2014), their Fig. 8, interpolated to our redshift and connected by dashed lines.