Table 3.

Median Gene Diversity at Polymorphic Nonsynonymous and Synonymous Sites and Median Q_non and Q_syn in 3 Bacterial Species

Species (no. of genes)	Gene Diversity		Qnon	Qsyn
	Nonsynonymous	Synonymous
Burkholderia pseudomallei (1,710)	0.375	0.377a	−0.501	−0.368b
Staphylococcus aureus (1,317)	0.272	0.294a	−0.438	−0.145b
Streptococcus pyogenes (875)	0.254	0.299a	−0.289	0.039b

^a Tests of the hypothesis that median gene diversity at nonsynonymous sites equals median gene diversity at synonymous sites: P < 0.001 (sign test).

^b Tests of the hypothesis that median Q_non equals median Q_syn: P < 0.001 (sign test).