Figure 7

Distribution of the AICc weights of segmented regression models with one breakpoint in simulated and observed data from the four populations. The selection experiment was simulated with the same parameters ans in Figure 6. For each simulation, segmented regression with a single breakpoint at each of the seven generations were fitted. The red bars represent the proportion of simulations in which the best fitted model corresponds to a breakpoint at the given generation. Similar results were obtained across simulations with the initial conditions indicated in Table 4. The grey bars represent the AICc weights computed by fitting segmented regression with a single breakpoint at each of the seven generations on the observed data of the two F252 (Early and Late Not Very Late) and MBS (Early and Late) experimental populations. These weights give the probability that the change in the rate of the response to selection occurred at generation G _i (2 ≤ i ≤ 7). Note that while in the simulations a higher probability is associated with a breakpoint occuring at G1, 3 out of the 4 experimental populations are consistent with a linear response to selection through time, i.e. breakpoint at G7.