Table 1.

The relationships of male traits, female age and laying date with yolk androgen concentration (PC1, based on yolk testosterone and androstenedione levels)

	DF	F	P
Reduced model
Male age	1, 77	4.42	0.039
Removed variables
Drost score	1, 75	0.24	0.62
Forehead patch size	1, 73	0.31	0.58
UV chroma of wing patch	1, 71	0.05	0.83
Female age	1, 75	0.00	0.96
Laying date	1, 76	0.23	0.63

The statistics for the removed variables are from a model in which they were added alone to the final reduced model

The error DF varies due to missing data for some of the variables

DF degrees of freedom; F F-statistic