Table 2.
Results of nested univariate analysis of variance (ANOVA) and multivariate analyses of covariance (MANCOVA) examining life-history and body shape variation of Gambusia spp. from four different clades, comparing sulfidic springs versus non-sulfidic habitats. The site(clade × H2S)-term was designated a random effect in all models. F-ratios in the MANCOVAs were approximated using Wilks’ values, partial variance was estimated using Wilks’ partial η 2, and terms with a partial variance at least half as strong as the strongest effect are given in bold for each model. Asterisks indicate terms that were tested using the mixed-model approach (see text)
| Effect | F | df | P | Partial variance | Relative variance |
|---|---|---|---|---|---|
| (a) SL (ANOVA) | |||||
| Sex | 817.5 | 1, 708 | < 0.001 | 0.127 | 0.516 |
| Clade | 5.0 | 3, 6 | 0.044 | 0.246 | 1.000 |
| H2S | 2.7 | 1, 6 | 0.15 | 0.052 | 0.211 |
| Site(Clade × H 2 S) | 17.2 | 6, 708 | < 0.001 | 0.127 | 0.516 |
| Sex × Clade | 5.8 | 3, 708 | 0.001 | 0.024 | 0.098 |
| Sex × H2S | 8.5 | 1, 708 | 0.004 | 0.012 | 0.049 |
| Sex × Clade × H2S | 30.5 | 3, 708 | < 0.001 | 0.114 | 0.463 |
| (b) Adult life histories (MANCOVA) | |||||
| SL | 2211.5 | 3, 702 | < 0.001 | 0.904 | 1.000 |
| Sex | 513.3 | 3, 702 | < 0.001 | 0.687 | 0.760 |
| Clade* | 41.3 | 6, 1342 | < 0.001 | 0.147 | 0.163 |
| H2S* | 3.4 | 2, 1121 | 0.0342 | 0.161 | 0.178 |
| Site(Clade × H2S) | 17.8 | 18, 1986 | < 0.001 | 0.132 | 0.146 |
| Clade × H2S* | 8.5 | 6, 1342 | < 0.001 | 0.096 | 0.106 |
| SL × Clade | 1.5 | 9, 1708.6 | 0.007 | 0.011 | 0.012 |
| Sex × Clade | 4.1 | 9, 1708.6 | < 0.001 | 0.017 | 0.019 |
| Sex × H2S | 15.5 | 3, 702 | < 0.001 | 0.062 | 0.069 |
| Sex × Clade × H2S | 7.3 | 9, 1708.6 | < 0.001 | 0.030 | 0.033 |
| (c) Offspring-related life histories (MANCOVA) | |||||
| SL | 69.9 | 3, 395 | < 0.001 | 0.347 | 0.569 |
| Stage of Development | 16.0 | 3, 395 | < 0.001 | 0.108 | 0.177 |
| Clade* | 22.3 | 6, 934 | < 0.001 | 0.297 | 0.488 |
| H 2 S | 54.6 | 2, 771 | < 0.001 | 0.609 | 1.000 |
| Site(Clade × H2S) | 24.9 | 18, 1117.7 | < 0.001 | 0.272 | 0.447 |
| Clade × H2S* | 5.2 | 6, 934 | < 0.001 | 0.124 | 0.203 |
| SL × Clade | 5.4 | 9, 961.5 | < 0.001 | 0.039 | 0.065 |
| SL × H2S | 3.4 | 3, 395 | 0.019 | 0.025 | 0.041 |
| SL × Clade × H2S | 2.0 | 9, 961.5 | 0.038 | 0.015 | 0.024 |
| Stage × Clade | 3.4 | 9, 961.5 | 0.0004 | 0.025 | 0.041 |
| Stage × H2S | 2.9 | 3, 395 | 0.034 | 0.022 | 0.036 |
| Stage × Clade × H2S | 2.4 | 9, 961.5 | 0.011 | 0.018 | 0.029 |
| (d) Body shape (MANCOVA) | |||||
| Centroid size | 125.0 | 7, 898 | < 0.001 | 0.512 | 0.651 |
| Sex | 129.8 | 7, 898 | < 0.001 | 0.504 | 0.640 |
| Clade* | 226.8 | 18, 4227 | < 0.001 | 0.787 | 1.000 |
| H 2 S* | 22.3 | 6, 2809 | < 0.001 | 0.403 | 0.513 |
| Site(Clade × H2S) | 13.2 | 63, 5063.7 | < 0.001 | 0.160 | 0.204 |
| Clade × H2S* | 19.4 | 18, 4227 | < 0.001 | 0.297 | 0.378 |