Table 2. Patterns of genetic and phenotypic covariance in sperm traits in guppies.
| Trait | Sperm head | Midpiece | Flagellum | Total sperm length | VAP | ALH | BCF | Sperm viability |
|---|---|---|---|---|---|---|---|---|
| Sperm head | — | −0.02 (0.26) | 0.87 (0.10) | 0.90 (0.07) | −0.17 (0.25) | −0.23 (0.29) | −0.08 (0.33) | −0.97 (0.06) |
| Midpiece | 0.13 | — | −0.34 (0.24) | 0.20 (0.26) | −0.84 (0.14) | −0.37 (0.29) | 0.78 (0.25) | 0.03 (0.26) |
| Flagellum | 0.37 | −0.37 | — | 0.85 (0.08) | 0.11 (0.26) | 0.01 (0.30) | −0.36 (0.31) | −0.85 (0.10) |
| Total sperm length | 0.55 | 0.23 | 0.81 | — | −0.35 (0.24) | −0.19 (0.31) | −0.01 (0.36) | −0.87 (0.09) |
| VAP | 0.03 | −0.14 | −0.01 | −0.09 | — | 0.85 (0.15) | −0.65 (0.27) | 0.07 (0.25) |
| ALH | 0.18 | −0.03 | 0.08 | 0.06 | 0.49 | — | −0.17 (0.44) | 0.12 (0.31) |
| BCF | −0.09 | 0.14 | −0.08 | −0.01 | −0.36 | −0.41 | — | 0.02 (0.33) |
| Sperm viability | −0.29 | 0.12 | −0.34 | −0.30 | 0.11 | −0.01 | 0.02 | — |
Abbreviations: ALH, amplitude of lateral head displacement; BCF, beat cross frequency; VAP, average path velocity.
Genetic correlations and REML estimates of s.e. (in parentheses) are listed above the diagonal; phenotypic correlations are listed below the diagonal. The significance of genetic correlations was tested using likelihood-ratio tests from models with fixed and unfixed covariance structures (significant values are highlighted in bold font).