Table 1.

Evolutionary selection analyses of scy genes among the cyanobacterial radiation, as gauged by the ratio of the number of non-synonymous substitutions per non-synonymous site (dN) to the number of synonymous substitutions per synonymous site (dS), according to various algorithms.

Algorithm	dN/dS Ratio
	scyA	scyD	scyE
Jukes and Cantor (1969)	0.22	0.97	0.61
Li et al. (1985)	0.24	0.90	0.57
Nei and Gojobori (1986)	0.40	0.99	0.72
Nei and Kumar (2000)	0.30	1.14	0.72
Pamilo and Bianchi (1993)	0.27	1.15	0.65