environment occurred 0.4 Gyr before quenching in the field, our models (described in §5) suggest that the intrinsic scatters should be lower by only $\sim$0.02 mag, rather than the $\sim$0.05 mag difference shown in Figure \[scatter\].

![The observed (green) and intrinsic (black) scatter in the rest-frame $U$-$V$ colors of the most massive, quiescent galaxies selected by their extinction-correct $U$-$V$ colors. The scatter due to measurement errors (blue) is subtracted from the observed scatter in quadrature. The vertical black error bars mark the 68% confidence intervals due to photometric errors and the grey filled region indicates how $\sigma_{U-V}$ changes when we raise and lower the horizontal selection limit in Figure 1 by $\pm$0.2 magnitudes. The dashed line is the expected evolution of the intrinic scatter due to passive evolution for galaxies that started forming stars at $z$=3 with a characteristic timescale for transformation into an early-type galaxy of 1.4 Gyrs, with a large burst of star formation before transforming. The observed $U$-$V$ data points used to calculate teh color scatter as a function of redshift are plotted in the bottom panel. We find that the scatter in $U$-$V$ increases towards higher redshift, where the intrinsic scatter is significantly higher than the 