Table 1.
Analysis of variance of the first and second principal components of gill size in lake whitefish from four lakes in Maine, USA, and Québec, Canada
| PC 1 Mass standardized | PC 2 Mass standardized | PC 1 Length standardized | PC 2 Length standardized | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| F | DF | P-value | F | DF | P-value | F | DF | P-value | F | DF | P-value | |
| Model | 3.05 | 7,31 | 0.015 | 4.82 | 7,31 | <0.001 | 5.21 | 7,31 | <0.001 | 4.05 | 7,31 | 0.003 |
| Lake | 5.81 | 3 | 0.003 | 0.81 | 3 | 0.494 | 4.36 | 3 | 0.011 | 1.42 | 3 | 0.255 |
| Species | 3.79 | 1 | 0.061 | 6.71 | 1 | 0.014 | 23.51 | 1 | <0.001 | 2.87 | 1 | 0.100 |
| Lake×Species | 0.05 | 3 | 0.986 | 8.04 | 3 | <0.001 | 0.44 | 3 | 0.724 | 7.07 | 3 | <0.001 |
The contribution of lake, species (dwarf, normal), and the interaction between lake and species were examined for both body mass and length standardized principal components of gill size. As outlined in the methods, principal component 1 (PC 1) exhibited positive loadings for all five gill metrics, whereas number of gill filaments was the primary factor influencing component two (PC 2). Significant P-values (P < 0.05) are indicated in bold.