Fig. 1.

The ranked relative abundance of 16S rRNA genes classified to genera in the family Caulobacteraceae in (a) sequencing libraries from a variety of environmental samples (b) averaged and plotted as stacked bar plots. In (a), the total number of samples are shown before and after removing those with fewer than 500 quality-filtered sequences. In (b), the lettering denotes statistically supported differences in the relative abundance of specifically Caulobacter (Tukey HSD; p < 0.001). Error bars represent the standard error of counts of all Caulobacteraceae