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Table 3 Relation between sperm functional traits and sperm design

From: Is sperm morphology functionally related to sperm swimming ability? A case study in a wild passerine bird with male hierarchies

  Before social status manipulation After social status manipulation
Fixed effects VCL Proportion of motile sperm VCL Proportion of motile sperm
Slope ± SD F (df1,df2) p Slope ± SD F (df1,df2) p Slope ± SD F (df1,df2) p Slope ± SD F (df1,df2) p
Intercept −29.64 ± 72.88    −4.79 ± 4.24    79.4 ± 73.83    −3.92 ± 4.28   
Social rank   3.13 (3,36) 0.037   5.62 (3,36.1) 0.003   1.08 (3,34.9) 0.37   0.89 (3,35.5) 0.45
 Subordinate 1 9.91 ± 5.56    0.94 ± 0.32    9.43 ± 6.15    0.59 ± 0.37   
 Subordinate 2 14.94 ± 5.84    0.89 ± 0.34    −0.48 ± 6.12    0.32 ± 0.36   
 Subordinate 3 8.96 ± 5.46    0.14 ± 0.32    2.03 ± 6.13    0.08 ± 0.37   
Sperm design 0.81 ± 1.33 0.7 (1,42.2) 0.41 −0.07 ± 0.08 2.87 (1,42.9) 0.1 0.37 ± 1.46 0.40 (1,47.9) 0.53 −0.08 ± 0.08 0.001 (1,44.5) 0.99
Time −0.37 ± 0.03 563.62 (1287) > 0.001 − 0.02 ± 0.001 367.22 (1287) > 0.001 −0.36 ± 0.03 617.62 (1282) > 0.001 −0.009 ± 0.001 238.64 (1282) < 0.001
Body mass 2.86 ± 1.83 2.36 (1,43.4) 0.13 0.09 ± 0.11 0.76 (1,44.2) 0.39 2.59 ± 1.83 1.92 (1,43.2) 0.17 0.01 ± 0.11 0.01 (1,46.9) 0.92
Tarsus length 0.98 ± 3.23 0.09 (1,45.5) 0.77 0.16 ± 0.19 0.66 (1,46.2) 0.42 −3.85 ± 3.63 1.10 (1,38) 0.30 0.22 ± 0.21 1.05 (1,41.1) 0.31
Social rank x Sperm design   1.06 (3,46.1) 0.37   3.09 (3,46.7) 0.036   1.03 (3,43) 0.39   1.46 (3,46) 0.24
 Subordinate 1 −1.24 ± 1.97    −0.05 ± 0.11    −2.11 ± 2.03    0.02 ± 0.12   
 Subordinate 2 −2.9 ± 1.92    0.12 ± 0.11    1.59 ± 2.02    0.17 ± 0.12   
 Subordinate 3 1.5 ± 1.68    0.24 ± 0.10    −1.6 ± 2.28    0.20 ± 0.13   
Social rank x Time   0.99 (3287) 0.4   8.83 (3287) > 0.001   1.34 (3282) 0.26   1.73 (3282) 0.16
 Subordinate 1 0.06 ± 0.04    0.005 ± 0.002    0.01 ± 0.04    −0.002 ± 0.002   
 Subordinate 2 0.001 ± 0.04    0.005 ± 0.002    0.06 ± 0.04    −0.004 ± 0.002   
 Subordinate 3 0.02 ± 0.04    0.01 ± 0.002    0.06 ± 0.04    −6.0 E-4 ± 0.002   
Sperm design x Time −0.01 ± 0.01 0.06 (1287) 0.81   1.83 (1287) 0.18 0 ± 0.01 5.78 (1282) 0.017 −2.7 E-4 ± 4.3 E-4 0.56 (1282) 0.45
Social rank x Sperm design x Time   4.34 (3287) 0.005 8.2 E-5 ± 4.8 E-4 2.4 (3287) 0.07   1.74 (3282) 0.16   1.55 (3282) 0.20
 Subordinate 1 0.02 ± 0.01    0.001 ± 7.1 E-4    −0.01 ± 0.01    −2.5 E-5 ± 6.2 E-4   
 Subordinate 2 0.04 ± 0.01    −3.5 E-5 ± 6.8 E-4    −0.02 ± 0.01    7.9 E-4 ± 6.0 E-4   
 Subordinate 3 0.001 ± 0.01    7.1 E-5 ± 6.0 E-4    0 ± 0.01    −5.1 E-4 ± 6.4 E-4   
  1. Estimates from linear mixed models, and F and p values from ANOVAs with Kenward-Roger approxi-mation to the degrees of freedom. Contrast are done against the dominant males. Bold p-values are significant (alpha = 0.05)