Table 1.

Pairwise comparisons of substitution rates

Species compared	Replacement substitution rate	Amino acid substitution rate	KA/KS ratio
Ga vs. Cm	Ga > Cm*†‡§	Ga > Cm**¶‖	5.0**
Ga vs. Tb	Ga > Tb*†‡§	Ga > Tb**¶‖	2.3*
Ga vs. Th	Ga > Th*†‡§	Ga > Th**¶‖	2.3*
Pb vs. Tb	Pb > Tb*§	Pb > Tb*¶‖	1.3
Pb vs. Th	Pb > Th*§	Pb > Th*¶‖	1.0

Only statistically significant results are shown (∗, P < 0.05; ∗∗, P < 0.01). 

Ga, G. acuticeps; Cm, C. mawsoni; Tb, T. bernacchii; Th, T. hansoni; Pb, P. borchgrevinki. 

^†Relative rate test according to Wu and Li (20). 

^‡ML test using codrates according to Muse and Gaut (21). 

^§Rate test using reconstructed ancestral sequences. 

^¶Relative rate test with amino acid distance (Poisson correction). 

^‖Relative rate test with amino acid gamma distance (parameter a = 0.3). K_A/K_S ratios relative to pairwise comparisons are also reported.