Table 2. Proportions of nucleotide differences at non-CG-susceptible 4-fold and FEI sites.

	Type of nucleotide change
	A↔T	A↔C	A↔G	T↔C	T↔G	C↔G
Four-fold sites	0.0175 (0.0021)	0.0272 (0.0017)	0.0827 (0.0030)	0.0753 (0.0029)	0.0270 (0.0019)	0.0298 (0.0017)
FEI sites	0.0259 (0.0007)	0.0327 (0.0007)	0.0924 (0.0012)	0.0880 (0.0011)	0.0332 (0.0007)	0.0316 (0.0007)

Entries are defined as for Table 1. Bootstrap SEMs are shown in parentheses.