Table 1.
Results of analyses of covariance to explain interspecific variation in immune function for raw data and phylogenetically independent contrasts. Interactions were dropped from the models when p > 0.10, but main effects were always retained.
| variables | raw data |
independent contrasts |
||||
|---|---|---|---|---|---|---|
| d.f. | F-value | p-value | d.f. | F-value | p-value | |
| (a) ignoring embryonic temperature effects (figure 2a) | ||||||
| inflammatory immune response (error d.f. = 28; R2 = 0.33) | ||||||
| site | 1 | 1.60 | 0.22 | 1 | 2.99 | 0.10 |
| loge body mass | 1 | 18.50 | <0.001 | 1 | 1.72 | 0.20 |
| loge embryonic period | 1 | 2.38 | 0.13 | 1 | 1.59 | 0.22 |
| natural antibody activity (error d.f. = 28; R2 = 0.20) | ||||||
| site | 1 | 0.42 | 0.52 | 1 | 0.75 | 0.39 |
| loge body mass | 1 | 4.63 | 0.04 | 1 | 0.68 | 0.42 |
| loge embryonic period | 1 | 0.18 | 0.67 | 1 | 0.03 | 0.88 |
| (b) accounting for embryonic temperature effects (figure 2b) | ||||||
| inflammatory immune response (error d.f. = 27; R2 = 0.59) | ||||||
| site | 1 | 1.29 | 0.27 | 1 | 1.42 | 0.24 |
| loge body mass | 1 | 10.43 | 0.003 | 1 | 1.23 | 0.28 |
| embryonic temperature | 1 | 11.64 | 0.002 | 1 | 5.95 | 0.022 |
| loge embryonic period | 1 | 14.81 | 0.001 | 1 | 7.78 | 0.010 |
| natural antibody activity (error d.f. = 25; R2 = 0.72) | ||||||
| site | 1 | 22.32 | <0.001 | 1 | 2.99 | 0.096 |
| loge body mass | 1 | 0.97 | 0.34 | 1 | 1.08 | 0.31 |
| embryonic temperature | 1 | 45.98 | <0.001 | 1 | 12.21 | 0.002 |
| loge embryonic period | 1 | 33.28 | <0.001 | 1 | 9.35 | 0.005 |
| site × embryonic temperature | 1 | 22.32 | <0.001 | 1 | 3.54 | 0.071 |
| site × loge embryonic period | 1 | 15.59 | 0.001 | 1 | 4.18 | 0.052 |