Table 2.

The six-candidate regression models describing how patterns of age-specific investment in calling effort depend on the juvenile acoustic environment that males experience. The models are listed in order of complexity, beginning with a null model where no age-specific patterns of calling investment were estimated (model 1), and ending with the most complex model where separate patterns were estimated for every combination of density and calling rate treatments (model 6). Presented for each model are the corresponding AIC scores and the AIC weights, where larger values indicate greater relative support for the given model in comparison to all other candidate models.

Candidate models for patterns of age-specific calling effort	Terms added	Total factors	AIC	AIC weight
(1) No aging curve	Treatment intercepts	0	15,249	<0.001
(2) Single curve for all treatments	Age	2	14,169	<0.001
	Age2
(3) Different curves for density treatments only	Density × Age	5	14,174	<0.001
	Density × Age2
(4) Different curves for calling rate treatments only	Calling rate × Age	5	14,138	0.067
	Calling rate × Age2
(5) Different curves for calling rate and density treatments independently	Density × Age	8	14,137	0.111
	Calling rate × Age
	Density × Age2
	Calling rate × Age2
(6) Different curves for every density and calling rate combination	Density × Calling rate × Age	11	14,133	0.821
	Density × Calling rate × Age2