Skip to main content

Table 2 Generalized estimating equations (A) and REML mixed models (B) investigating the factors that affected male competition (measured during Focal Follows)

From: Females sample more males at high nesting densities, but ultimately obtain less attractive mates

A.

Behaviour

Fixed effect

Wald Chi-Square

df

P

Competition received

Male Density

0.28

1

0.59

 

Day of Season

16.84

3

<0.01

 

Nesting Status

0.05

1

0.83

Competition initiated

Male Density

0.92

1

0.34

 

Day of Season

6.61

3

0.08

 

Nesting Status

4.38

1

0.04

B.

    

Behaviour

Fixed Effect

F

df

P

Number of behaviours received

Male Density

0.43

1, 31.94

0.51

 

Day of Season

5.69

1, 27.51

0.02

 

Nesting Status

0.10

1, 109.9

0.76

Number of behaviours initiated

Male Density

0.01

1, 32.2

0.91

 

Day of Season

4.51

1, 25.23

0.04

 

Nesting Status

1.00

1, 114

0.32

Competition score

Male Density

0.21

1, 33.07

0.65

 

Day of Season

0.08

1, 30.12

0.78

 

Nesting Status

8.85

1, 107.8

<0.01

Number of competitors

Male Density

0.61

1, 31.8

0.44

 

Day of Season

8.81

1, 29.2

<0.01

 

Nesting Status

3.19

1, 106.4

0.08

  1. GEEs investigated competition received (males receiving vs. not receiving aggression from non-focal males) and competition initiated (males initiating vs. not initiating competition with non-focal males), and REML mixed models investigated the sum number of behaviours initiated and received, how far competition escalated (the competition score), and the number of males physically competing. In the GEEs, we treated time as a categorical variable with four levels (dividing the season into 2 week blocks) because of lost degrees of freedom. In all other models, day of season was a continuous variable. Replicate pool was a random effect in all models and significant results are indicated in bold