Figure 2.

Schematic illustration of factors affecting SGD under the unified grouping scheme We use a small number of genes to represent ratios (∼57% and ∼70% on average for the non-polC and polC groups, respectively) of conserved genes between LeS (solid green arrows) and LaS (solid blue arrows). There are three possible scenarios where specific changes alter LesGP: biased gene rearrangement with two genes (open blue arrows) transferred to LeS from LaS increases LesGP from 57% to 71% (A); biased gene loss with three events (open blue arrows) from LaS leads to the increase of LesGP from 57% to 73% (B); biased gene acquisition, such as adding 11 genes to LeS but adding 2 to LaS (pink arrows and arrow-heads), results in the change of LesGP from 57% to 70% (C).