Figure 3. Evolution of plasmid cost into benefit rather than a change in segregational loss frequency facilitated improved plasmid persistence.

The effect of the plasmid on host fitness, i.e. plasmid cost (a), and segregational loss frequency (b) were jointly estimated using conjugated data from plasmid persistence assays and competition experiments using the SS model for the ancestral host-plasmid pairs H_AP_A and their respective evolved H_EP_E clones from replicate populations A to C. Evolved clones in each population are ordered sequentially from 1 to 3. For each conjugated dataset n = 3. The vertical lines represent deviations in the model output. The large deviations indicate that a wide range of maximum likelihood estimates are possible for that parameter. The asymmetry of the lines is due to the date being plotted on a log scale.