Table 2. CODEML model comparisons and associated hypothesis that is being tested are described.
| Model comparison | Log ratio test | Testing for |
|---|---|---|
| Model 0 vs Model 1a | χ2=40.04, P<0.05 | Non-neutrality |
| Model 1a vs Model 2a | χ2=0, NS | Positive selection |
| Model M7 vs Model M8 | χ2=1.43, NS | Positive selection |
| Model 0 vs branch model 2 | χ2=20.55, P<0.001 | Higher ω ratios in pre-specified foreground branches (coastal branches here) |
| MAnull vs branch-sites-model-A-modified | χ2=2327.9, P<0.001 | Positive selection or relaxation of selective constraint affecting certain sites in pre-specified foreground branches (coastal branches here) |
| Model 1a vs branch-sites-model-A-modified | χ2=18.99, P<0.001 | Positive selection (if ω 2a and/or ω2b>1 in foreground), or relaxation of selective constraint (if ω 2a and/or ω2b⩽1 in foreground) affecting certain sites in pre-specified foreground branches (coastal branches here) |
Bold font indicates a significant (P<0.05) log ratio test and support for the stated hypothesis.