Cell density after 24 hours of growth in stressful conditions increased with increasing mutation rate, except for MR^XL replicate populations.

<p>We measured the cell density of the MR^S, MR^M, MR^L, and MR^XL evolved replicate populations relative to the ancestor (vertical axis) at generation 1000 in (A) medium supplemented with nitrofurantoin (2.2 μg/mL) and in (B) acidic medium (pH 5.25). The MR^S, MR^M, MR^L replicate populations performed better with increasing mutation rate, except for the MR^XL replicate populations which performed worst among all populations. See <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1007324#pgen.1007324.s012" target="_blank">S12 Fig</a> for data on additional timepoints, and nitrofurantoin and pH conditions. Different colors distinguish data from the MR^S (blue), MR^M (yellow), MR^L (orange), and MR^XL (red) strains.