Table 1.
Results of Principal component analysis (PCA) for the European minnow sperm quality (PC1, “motility”) and curvature of the sperm swimming trajectory (PC2, “trajectory”). Highest loadings are indicated in boldface
| Measurement | PC1 (motility) | PC2 (trajectory) |
|---|---|---|
| VSL | 0.889 | 0.420 |
| VCL | 0.982 | −0.006 |
| VAP | 0.976 | 0.127 |
| % static | −0.914 | −0.006 |
| % rapid | 0.975 | 0.023 |
| LIN | 0.210 | 0.965 |
| STR | −0.060 | 0.986 |
| Eigenvalues | 4.54 | 2.10 |
| % of variance | 64.9 | 29.9 |
| Cumulative % | 64.9 | 94.8 |
VSL, straight line velocity; VCL, curvilinear velocity; VAP, average path velocity; % static, proportion of immotile cells; % rapid, proportion of rapid cells; LIN, linearity of the swimming trajectory (VSL/VCL); STR, straightness of the swimming trajectory (VSL/VAP).