Table 5 Factor loadings of three body size variables on the first two principal components in Principal Component Analyses of a) male and b) female teydea and polatzeki Blue Chaffinches, and their eigenvalues, percentage of variance explained, and F-statistics

Wing length

0.616

−0.189

0.636

−0.286

Tail length

0.582

−0,544

0.626

−0.351

Bill length

0.530

0.817

0.451

0.892

Eigenvalue

2.285

0.520

2.076

0.727

Variance explained

76.2 %

17.3 %

69.2 %

24.2 %

Test of difference between taxa

F _1,71  = 298.04, P < 0.001

F _1,71  = 0.17, P = 0.68

F _1,54  = 82.13, P < 0.001

F _1,54  = 6.58, P = 0.013