Table 1.

Mean values of reproductive isolation at 9 examined barriers (1 postmating prezygotic [pollen-pistil], and 8 postzygotic) and 2 cumulative measures, along with their absolute and relative contributions to total isolation.

	Pollen-Pistil (n=42)	Fruit Set (n=44)	Fruit Size (n=33)	Seed Set (n=33)	Seed Viability (n=33)	F1 Pollen Viability (n=9)	F1 Fruit Set (n=9)	F1 Fruit Size (n=6)	F1 Seed Set (n=6)	Total Post-Zygotic (n=44)	Total (n=44)
Mean RI	0.070	0.682	0.429	0.449	0.879	0.322	0.388	0.205	0.408	0.971	0.971
Mean Absolute Contribution to Total	0.079	0.589±	0.155	0.077	0.133	0.012	−0.025	−0.057	0.044	0.921	1.000
Mean Relative Contribution to Total	0.079	0.588±	0.148	0.083	0.228	0.012	−0.062	−0.121	0.084	0.921	1.000
Mean Asymmetry	0.066*	0.496***	0.463**	0.562**	0.153*	0.057	0.292*	0.506*	0.168	0.064	0.064

^±Fruit Set has the highest absolute and relative contribution to total isolation (ANOVA, p< 0.00001; Tukey HSD p< 0.00001).

Sample sizes refer to number of species pairs. RI values between reciprocal crosses were often highly asymmetric:

^*p<0.05,

^**p<0.001;

^***p<0.0001 (one-sample t-test).