Scatterplot of codon usage.

<p>The scratterplot of codon usage summary statistics N_c and N_c′ against the proportion of G or C nucleotides at the 3^rd position of synonymous codons (GC_3s), showing greater codon usage bias in the bat SaV genome relative to other SaV genomes. Unlike the porcine enteric caliciviruses, the observed difference in codon usage bias persists with adjustment of background nucleotide composition (N_c′).