The evolutionary rates of the three antibody lineages decrease over time.

The evolutionary rates for the stages of the three lineages were calculated using BEAST2. The mean evolutionary rates for the VRC26, CH103, and VRC01 lineages decreased about 80%, 45%, and 35% respectively over their study periods. However, the observed evolutionary rate decrease is not statistically significant for clade 08 light chain, clade H3, and L3. Each stage is labeled with the format of lineage name, chain name, and stage. Because clades of the VRC01 lineage showed more than 30% divergence from each other, we chose four representative clades (03+06, 08, H3, and L3) and calculated their evolutionary rates separately. The mean and 95% HPD are shown for each stage. Stages from the same chain of a lineage are connected to reveal longitudinal trends. The evolutionary rates of heavy chains and light chains are colored blue and red respectively.