(A) Clusters of concordantly evolving sites. Graph vertices represent sites, and edges represent concordantly evolving pairs (Appendix 1—table 7). The graph consists of 13 connected components, 8 of which contain just a single edge. Site pairs that were among the set of the best scoring pairs predicted for the alternative UShER (Turakhia et al., 2021) topology (FDR <10%, Table 1) are marked by asterisks. (B) Concordantly evolving sites among the lineage-defining sites of Alpha, Beta, Gamma, Delta (B.1.617.2+AY.*) and Omicron (BA.1) VOCs (Hodcroft, 2021). Concordantly evolving sites are colored in accordance with the clusters in panel A. Sites with fewer than 2 mutations which were not included in the analysis are in gray.