Table 1.

Table summarizing codon-based tests for positive selection

Likelihood models	Statistical test	P-value	Estimate for ω >1	Proportion of sites ω >1	Codon sites ω >1
M1a vs M2a	18.212	0.00011	3.41529	0.20074	121,158,159
M7 vs M8	23.862	6.58E-06	3.02509	0.26839	121,158,159,161,163,164
M8a vs M8	15.922	3.30E-05

ω = (dN / dS) where dN represents the number of non synonymous substitutions and dS the number of synonymous substitutions. Numbers of codon sites refer to position in the reading frame.