Table 2 Summary of linear mixed models of egg shape (sphericity) of blue tits in relation to year, site, clutch size and egg volume. Two separate models are shown: (i) with year as a categorical variable and (ii) with year as a continuous variable. Clutch ID included as a random effect

76.54 ± 1.03

1;1698.2

9859.9

<  0.0001

11;764.9

1.5

0.118

3.49 ± 0.96

1;8067.3

13.2

<  0.0001

1;785.0

0.7

0.796

−0.68 ± 0.14

1;8484.1

21.6

<  0.0001

−2.37 ± 0.81

1;8483.2

8.7

0.003

1;757.4

0.001

0.999

1;8408.8

0.008

0.928

11;762.6

0.6

0.837

11;771.9

0.9

0.562

11;8299.4

1.2

0.284

1;775.6

3.5

0.061

1;775.1

0.4

0.503

3.57 ± 0.95

1;8113.6

13.9

<  0.0001

1;795.1

0.404

0.525

−0.68 ± 0.13

1;8498.7

21.8

<  0.0001

−2.41 ± 0.81

1;8495.3

8.9

0.003

1;788.3

0.2

0.901

1;794.5

0.2

0.681

1;8374.0

0.695

0.405

1;8455.2

1.9

0.163

1;793.1

3.4

0.063