Table 1.

Comparison of animal models including different additive genetic variation and covariation terms for baseline and stress-induced corticosterone levels in nestling barn owls

	Genetic		DIC	∆DIC
	Variance	Covariance
Models without covariates
Model 1	Yes	Yes	8,407.4	0
Model 2	Yes	No	8,661.8	254.4
Model 3	No	No	8,743.0	335.6
Models including covariates
Model 1	Yes	Yes	8,144.5	0
Model 2	Yes	No	8,272.4	127.9
Model 3	No	No	8,367.7	223.2

Note: In model 1, we estimated the additive genetic variances for baseline and stress-induced corticosterone levels and their genetic covariation. In model 2, we estimated the additive genetic variances for baseline and stress-induced corticosterone levels but considered that genetic covariance equals zero. Finally, in model 3, we considered no additive genetic (co)variance for corticosterone levels. In each model, we added the identity of the brood and year as random factors. Shown are the DIC (deviation information criteria) values for each model and the differences of each model to the model with the lowest DIC (∆ DIC) for models without or with covariates included