More ornamented females produce higher-quality offspring in a socially monogamous bird: an experimental study in the great tit (Parus major)

Table 1 Summary of statistical models

	Body mass		Tarsus length		Immune response		Nestling survival
Factor	F	P	F	P	F	P	χ²	P
Year	45.4	<0.001	11.1	0.001	2.4	0.124	0.2	0.701
Hatching date	2.6	0.113	2.1	0.157	14.8	<0.001	0.2	0.689
Tarsus length	38.5	<0.001	----	----	----	----	----	----
Fledging mass	----	----	----	----	12.3	0.001	3.3	0.068
Brood size manipulation	9.3	0.003	1.9	0.170	1.7	0.201	0.3	0.604
Breast stripe area, F	<0.1	0.847	1.5	0.227	2.1	0.149	0.1	0.753
Carotenoid chroma, F	<0.1	0.929	1.3	0.258	0.2	0.649	1.0	0.321
Cheek immaculateness, F	<0.1	0.873	0.2	0.666	4.3	0.043	1.0	0.327
Age, F	0.1	0.710	0.9	0.339	1.4	0.236	0.1	0.770
Breast stripe area, G	6.6	0.012	1.9	0.170	0.1	0.813	<0.1	0.913
Carotenoid chroma, G	1.4	0.235	3.2	0.080	0.2	0.633	3.6	0.057
Cheek immaculateness, G	0.2	0.677	<0.1	0.844	5.8	0.019	2.8	0.096
Age, G	0.2	0.634	1.6	0.211	3.7	0.058	0.1	0.814
Tarsus length, G	----	----	10.3	0.002	----	----	----	----

Results of linear models (body mass, tarsus length, immune responsiveness, DF = 11, 66) and the generalized linear model (nestling survival, DF = 11, 64) analyzing effects of year, season, nestling morphology, brood size manipulation, and foster (F) and genetic (G) mothers' traits on offspring performance. Statistically significant factors are highlighted in bold. ---- means that a particular factor was not included in the model.

ISSN: 1742-9994