Figure 3

Bat and pangolin coronaviruses from the same ___location are more closely related than those from elsewhere. (a) The Bayesian species tree for human, bat, pangolin, and MERS coronavirus from StarBeast (Materials and Methods). (b) The Bayesian species tree for human, bat_China, bat_others, pangolin_guangdong, pangolin_guangxi, and MERS coronavirus from StarBeast. The numbers at the internal nodes of the species tree are 95% highest posterior density (HPD) interval for the depth of the internal node. The lower bound on the time of divergence of bat, human, and pangolin coronaviruses is (.0023/3)/(0.0002) = 4 year, using a 1/3 of a year as the length of the early pandemic as a calibration point for the lower bound in variation of 0.0002 in humans in panel A. The time of divergence of bat, human, and pangolin coronaviruses is (0.0041/3)/(0.0004) = 3.42 year, using a 1/3 of a year as the length of the early pandemic and the posterior mean branch lengths of the (pangolin, (human, bat)) node of .0041 and the (human, bat) node of 0.0004.