Appendix 1—table 2. X chromosome, and X/A ratio, for expectation of Patterson’s D.

X/A ratio of Ne	Rationale	E[D]	X/A ratio of D
0.75	1:1 sex ratio, random mating, etc.	0.094	1.309
0.656	Observed X/A nucleotide diversity in D. mauritiana	0.106	1.479
0.778	Observed X/A nucleotide diversity in D. simulans	0.091	1.265