Table 3.
Positive selection tests.
| Hypothesis | Change | Variation in ω | Background ω | Change ω |
|---|---|---|---|---|
| H0 | None | none | 0.111 | n/a |
| H1 | Episodic | branch a† only | 0.110 | 0.293 |
| H2 | Episodic | branch b† only | 0.110 | undef (dN = 14.4, dS = 0) |
| H3* | shift | all in cv2C‡ | 0.090 | 0.154 |
| H4* | shift | all in cv2C + branch b† | 0.088 | 0.158 |
| H5* | shift + episodic | all in cv2C, branch b† different | 0.087 | undef (dN = 14.1, dS = 0) |
* rate in test branch significantly different than background
† Branches a and b refer to Fig 6.
‡ cv2C = boxed cv 2 Clade in Fig 6.
Episodes or shifts in positive selection associated with the evolution of digestive function in bivalve i-lysozymes were tested.