Results of the model selection process.

Models are phylogenetic generalized least square regressions with either climatic niche position or breadth as the response variable. Fixed predictors included migratory status (migr), age of first breeding (AFB), and either habitat niche position (HPI) or breadth (SSI) according to the model. The intercept is noted γ; k corresponds to the number of model parameters. The ΔAICc refers to the difference between the AICc of model i and that of the model with the lowest AICc value. The column “weight” refers to AICc weights, which were used to compute the averaged coefficients of the fixed effects.