Table 1.

Numbers of observed pair matings and estimates of sexual isolation across experimental designs.

		Number of matings
Experimental Design	Number of replicate trials	OO	OV	VO	VV	IPSI ± 1SD	P - value
Expt. 1: No-choice	122	23	23	13	22	0.132 ± 0.114	0.252
Expt. 2: Female-choice	90	23	20	9	28	0.310 ± 0.108	0.004*
Expt. 3: Multiple-choice	6	55	34	35	55	0.223 ± 0.074	0.005*

*Indicates non-random mating, i.e. significant premating isolation