Table 1.
Analyses of life-history traits. Linear-mixed models were used with lake type, predator treatment, and generation entered as fixed effects. Lake (nested within lake type) and clone (nested within lake) (and ‘lake × treatment’ and ‘clone × treatment’ interactions) were entered as random effects. The denominator degrees of freedom are displayed after each F-value. Significant (p < 0.05) results are displayed in italics.
| d.f. | age at maturation F (d.f.) | size at maturation F (d.f.) | clutch size F (d.f.) | intrinsic rate of increase (r) F (d.f.) | |
|---|---|---|---|---|---|
| fixed effects | |||||
| generation | 1 | 3.79+ (11.9) | 18.59*** (1 269) | 6.67* (1 242) | 0.14n.s. (12.5) |
| lake type | 2 | 0.02n.s. (15.3) | 1.01n.s. (6) | 0.98n.s. (6) | 1.92n.s. (12.5) |
| predator | 1 | 4.58* (49.2) | 10.1** (1 270) | 7.26** (1 243) | 1.39n.s. (475) |
| generation × lake type | 2 | 2.8+ (10.4) | 0.01n.s. (1 269) | 2.26n.s. (1 242) | 2.85+ (12.5) |
| generation × predator | 1 | 1.08n.s. (49.1) | 7.54** (1 269) | 0.77n.s. (1 243) | 1.27n.s. (475) |
| predator × lake type | 2 | 2.94+ (1 273) | 2.92+ (1 270) | 0.77n.s. (1 243) | 1.23n.s. (475) |
| generation × lake type × predator | 2 | 5.17** (1 272) | 1.16n.s. (1 269) | 1.14n.s. (1 243) | 2.98+ (475) |
| random effects | |||||
| lake (lake type) | 1 | 1.16n.s. | 1.27n.s. | 1.03n.s. | 0.9n.s. |
| clone (lake type) | 1 | 3.53*** | 5.82*** | 4.07*** | — |
| lake (lake type) × predator | 1 | 1.09n.s. | 0.06n.s. | 1.56n.s. | 0.44n.s. |
| lake (lake type) × generation | 1 | 1.69+ | 0.52n.s. | 1.58n.s. | 1.34n.s. |
| lake (lake type) × predator × generation | 1 | 1.5n.s. | 0.54n.s. | 1.43n.s. | 1.07n.s. |
| clone (lake) × predator | 1 | 0.32n.s. | 0.76n.s. | 0.9n.s. | — |
| clone (lake) × generation | 1 | 1.55n.s. | 0.1n.s. | 0.96n.s. | — |
| clone (lake) × predator × generation | 1 | 1.22n.s. | 1.76+ | 0.45n.s. | — |
±0.05 < p < 0.1.
*p < 0.05.
**p < 0.01.
***p < 0.001.
non-significant (n.s.) – p > 0.05.