Table 1.

Rate of molecular substitution in Cardamine.

	C. impatiens		C. resedifolia
	n a	mean (SE)b	n a	mean (SE)b	P c
dN	2913	0.0073 (0.0002)	2913	0.0083 (0.0002)	0.0001
dS	2913	0.0592 (0.0007)	2913	0.0665 (0.0010)	0.1830
dN/dS	2847	0.1763 (0.0058)	2875	0.1632 (0.0044)	3 × 10-9

^a Number of genes.

^b Mean and standard error.

^c Wilcoxon test probability after correcting for gene length (partial correlation)