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Table 4 Relation between sperm functional traits and total sperm length

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 −43.87 ± 71.08    −6.05 ± 4.18    75.36 ± 74.99    −3.86 ± 4.28   
Social rank   3.04 (3,36.1) 0.041   5.51 (3,36.1) 0.003   1.04 (3,34.9) 0.39   0.87 (3,35.5) 0.46
 Subordinate 1 10.06 ± 5.61    0.97 ± 0.33    9.73 ± 6.29    0.59 ± 0.37   
 Subordinate 2 15.42 ± 5.87    0.94 ± 0.34    −0.42 ± 6.26    0.32 ± 0.37   
 Subordinate 3 9.15 ± 5.51    0.17 ± 0.32    2.14 ± 6.27    0.07 ± 0.37   
Sperm total length 1.64 ± 1.45 0.0003 (1,47.1) 0.98 −0.11 ± 0.08 0.68 (1,47.2) 0.41 0.63 ± 1.43 0.1 (1,47.7) 0.76 −0.08 ± 0.08 0.001 (1,46.3) 0.99
Time −0.37 ± 0.03 561.43 (1287) > 0.001 − 0.02 ± 0 357.45 (1287) > 0.001 −0.36 ± 0.03 617.31 (1282) > 0.001 −0.01 ± 0 235.71 (1282) > 0.001
Body mass 3.19 ± 1.79 3.05 (1,42.8) 0.09 0.09 ± 0.11 0.75 (1,42.9) 0.39 2.95 ± 1.88 2.36 (1,42.8) 0.13 0.01 ± 0.11 0.01 (1,45.9) 0.91
Tarsus length 1.24 ± 3.23 0.14 (1,46.3) 0.71 0.22 ± 0.19 1.31 (1,46.4) 0.26 −4.16 ± 3.74 1.21 (1,38.6) 0.28 0.22 ± 0.22 0.97 (1,40.9) 0.33
Social rank x Sperm total length   1.47 (3,44.9) 0.23   3.25 (3,45) 0.030   0.7 (3,44) 0.55   1.16 (3,46.4) 0.34
 Subordinate 1 −3.26 ± 2.06    0.04 ± 0.12    −3.03 ± 2.49    0.02 ± 0.14   
 Subordinate 2 −4.37 ± 2.01    0.17 ± 0.12    0.43 ± 2.07    0.12 ± 0.12   
 Subordinate 3 0.2 ± 1.88    0.28 ± 0.11    −0.9 ± 2.23    0.19 ± 0.13   
Social rank x Time   0.98 (3287) 0.40   8.59 (3287) > 0.001   1.34 (3282) 0.26   1.71 (3282) 0.17
 Subordinate 1 0.06 ± 0.04    0.005 ± 0.002    0.01 ± 0.04    −0.002 ± 0.002   
 Subordinate 2 0 ± 0.04    0.01 ± 0    0.06 ± 0.04    −0.004 ± 0.002   
 Subordinate 3 0.02 ± 0.04    0.01 ± 0    0.06 ± 0.04    −0.001 ± 0.002   
Sperm design x Time −0.02 ± 0.01 0.02 (1287) 0.89 − 0.0003 ± 0.0005 0.02 (1287) 0.89 0 ± 0.01 3.78 (1282) 0.053 −0.0004 ± 0.0004 0.20 (1282) 0.65
Social rank x Total length x Time   3.96 (3287) 0.009   0.38 (3287) 0.76   2.35 (3282) 0.07   0.49 (3282) 0.69
 Subordinate 1 0.02 ± 0.01    0.0007 ± 0.0008    −0.01 ± 0.01    −0.0001 ± 0.0007   
 Subordinate 2 0.04 ± 0.01    0.0001 ± 0.0007    −0.03 ± 0.01    0.0006 ± 0.0006   
 Subordinate 3 0.01 ± 0.01    0.0005 ± 0.0007    −0.01 ± 0.01    0.0003 ± 0.0006   
  1. Estimates from linear mixed models, and F and p values from ANOVAs with Kenward-Roger approximation to the degrees of freedom. Contrast are done against the dominant males. Bold p-values are significant (alpha = 0.05)