Table 2. Fit of the GLMMs (delta AIC relative to the best model) in predicting individual prosociality in those subjects from groups without ceiling effects (CJ only) and in all subjects. In italics the model with the best fit.

Model	Factors/interactions included in the model	dAIC Only callithrix	dAIC All subjects
1	[Role]	24.7	24.9
2	[Experience]	42.8	45.8
3	[Helper sex distribution]	47.3	50.9
4	[Role], [Experience]	20.4	20.5
5	[Role], [Experience], [Role]* [Experience]	0	0
6	[Role], [Helper sex distribution]	26	27
7	[Role], [Helper sex distribution], [Role]* [Helper sex distribution]	21.1	25.1
8	[Experience], [Helper sex distribution]	44.4	48.1
9	[Experience], [Helper sex dist.], [Experience]* [Helper sex dist.]	47.8	51.4