Fig. 3: Evolution of B.1.596 viruses in white-tailed deer.

a, Bayesian time-scale MCC tree inferred for the cluster of 7 B.1.596 viruses identified in white-tailed deer at site 1, the 46 most closely related human B.1.596 viruses, and a random sampling of other B.1.596 viruses observed in the USA during November 2020 to March 2021. Tips are shaded by location state (host species and geography). Branches are shaded by the location state inferred from an ancestral reconstruction. Posterior probabilities are provided for key nodes. Cartoons indicate the host-switch branch where human-to-deer transmission may have occurred, followed by putative deer-to-deer transmission within site 1. The estimated timing and location state probability is provided for key nodes defining the host-switch branch. b, Clade-defining amino acid changes observed in all 7 B.1.596 deer viruses are listed. c, The E484D substitution in the spike protein’s receptor-binding motif (RBM) is shown in one of the B.1.596 deer viruses (OH-OSU-340). NTD, N-terminal domain; RBD, receptor-binding domain.