Fig. 1From: Exclusivity offers a sound yet practical species criterion for bacteria despite abundant gene flowCommon measures of the species rank exhibit widely different correlations with gene content similarity in Streptomycetaceae. The 16S rRNA sequence showed little correlation with gene content similarity (R2 = 0.38), whereas the rpoB gene sequence displayed good correlation (R2 = 0.75). Two genome-wide measures of similarity, average nucleotide identity (ANI) and alignment fraction (AF), were strongly correlated with gene content similarity. Horizontal dashed lines denote commonly used species-level cutoffs for each measure (e.g., > 97% 16S sequence identity)Back to article page