Fig. 4

A Bar graphs indicating the frequency of Y. pestis DFR genomovars in the Qinghai-Tibet Plateau. Correlation plot between genetic diversity and human plague outbreaks/episodes. B Correlation scatter plot between the genetic diversity and residual plague outbreak for microsatellite clustering results. For the purpose of plotting, the residual plague outbreak for each site was calculated by using a mixed-effect generalized linear model to control for the random effect of clustering results (covariates in the statistical analysis are reported in the text). Each dot represents a population. The gray area represents the 95% confidence interval