Table 1. Results of two-ratio model tests of selection pressure on the Tat gene in bats.

Modela	npb	ℓ	ω0 c	ωFix c	ModelCompared	2Δℓ	P-valued
0. One ratio: ω0	55	−8406.72	0.165	= ω0
1. Two ratios: ω0, ωA	56	−8394.02	0.153	0.585	1 vs. 0	25.398	<0.001
2. Two ratios: ω0, ωB	56	−8403.56	0.166	0.0001	2 vs. 0	6.321	>0.05
3. Two ratios: ω0, ωC	56	−8406.72	0.165	0.169	3 vs. 0	0.001	>0.05
4. Two ratios: ω0, ωD	56	−8406.72	0.165	0.0001	4 vs. 0	0.001	>0.05
5. Two ratios: ω0, ωE	56	−8406.51	0.165	0.078	5 vs. 0	0.422	>0.05
6. Two ratios: ω0, ωF	56	−8406.62	0.164	0.237	6 vs. 0	0.187	>0.05

^aSee Figure 1B for branch labels.

^bnp, number of parameters.

^cω_Fix (ω_A, ω_B, ω_C, ω_D, ω_E and ω_F) and ω₀, are the ω ratios for branches A, B, C, D, E, F and other branches, respectively.

^dThe P-value of each test was multiplied by six (tested branches) to correct for multiple testing.