Table 2.

Numbers of synonymous (d_S) nucleotide substitutions per synonymous site and nonsynonymous (d_N) nucleotide substitutions per nonsynonymous site between sister pairs of dsx genes of Diptera.

Species comparison	Common		Female-specific		Male-specific
	dS ± S.E.	dN ± S.E.	dS ± S.E.	dN ± S.E.	dS ± S.E.	dN ± S.E.
Anastrapha fraterculus Sp3 vs. A. Serpentina	0.0000 ± 0.0000	0.0031 ± 0.0031	0.0000 ± 0.0000	0.0147 ± 0.0148	0.0818 ± 0.0314	0.0085 ± 0.0060
Anastrepha fraterculus Sp2 vs. A. Sororcula	0.0256 ± 0.0068	0.0077 ± 0.0035	0.0000 ± 0.0000	0.0000 ± 0.0000	0.0223 ± 0.0158	0.0042 ± 0.0043
Anastrepha striata vs. A Bistrgiata.	0.0144 ± 0.0083	0.0031 ± 0.0022	0.0000 ± 0.0000	0.0146 ± 0.0146	0.0225 ± 0.0160	0.0042 ± 0.0042
Batrocera tryoni vs. B. Dorsalis	0.1249 ± 0.0261	0.0070 ± 0.0034	0.0000 ± 0.0000	0.0000 ± 0.0000	0.0458 ± 0.0231	0.0042 ± 0.0042
Drosophila pseudoobscura vs. D. Persimilis	0.0343 ± 0.0109	0.0011 ± 0.0011	0.0000 ± 0.0000	0.0000 ± 0.0000	0.0256 ± 0.0149	0.0031 ± 0.0031
Drosophila yakuba vs. D. erecta	0.1330 ± 0.0229	0.0163 ± 0.0043	0.0000 ± 0.0000	0.0000 ± 0.0000	0.1482 ± 0.0511	0.0090 ± 0.0052
Drosophila simulans vs. D. sechellia	0.0351 ± 0.0112	0.0034 ± 0.0019	0.0000 ± 0.0000	0.0000 ± 0.0000	0.0491 ± 0.0202	0.0030 ± 0.0030
Mean	0.0523 ± 0.0000	0.0060 ± 0.0020a	0.0000 ± 0.0000b	0.0042 ± 0.0027	0.0565 ± 0.0174	0.0052 ± 0.0010a

Paired t-tests of the hypothesis that mean d_S equals mean d_N:

^aP < 0.05.

Paired t-tests of the hypothesis that mean d_S or d_N equals the corresponding value for the common domain:

^bP < 0.05.