Table 4. Average synonymous (dS) and nonsynonymous (dN) substitutions per site and dN/dS ratios for genes located inside (IR) or outside (CR) the fixed inverted region in Muller elements A and E in D. arizonae (ar), D. mojavensis (mo), and D. navojoa (na).

	dN			dS			dN/dS
	ar-mo	ar-na	mo-na	ar-mo	ar-na	mo-na	ar-mo	ar-na	mo-na
Muller A
Genes in IR	346	387	387	346	387	387	346	387	387
Genes in CR	666	760	759	666	760	759	666	760	759
Median for IR	0.005	0.016	0.016	0.049	0.149	0.149	0.108	0.110	0.118
Median for CR	0.004	0.014	0.014	0.048	0.149	0.148	0.109	0.104	0.108
P-value	0.234	0.382	0.268	0.094	0.679	0.966	0.720	0.379	0.308
Muller E
Genes in IR	859	930	946	859	930	946	859	930	946
Genes in CR	277	310	312	277	310	312	277	310	312
Median for IR	0.005	0.012	0.012	0.0616	0.1487	0.148	0.098	0.09	0.092
Median for CR	0.005	0.013	0.014	0.0561	0.1628	0.1614	0.103	0.092	0.088
P-value	0.591	0.420	0.309	0.0002a	0.0001a	0.0005a	0.622	0.501	0.903

^aSignificantly different (P < 0.05).