Fig. 3

The maximum a posteriori estimate of the tMRCA with 95% highest posterior density intervals as inferred using BEAST. These are compared to equivalent estimates from data sets with the sampling sequences randomly permuted (clusters of sequences).The Y-axis indicates the tMRCA and the X-axis shows randomization of the data set, with the non-randomized data set (i.e., with dates correctly assigned to sequences) shown between horizontal yellow lines. The circles represent the mean tMRCA and the error bars show the 95% credible intervals