Table 1.

Results of GLMMs on response to increased task demands. Non-significant interactions were eliminated from the models. Non-significant terms are shown for information; their exclusion does not qualitatively change the results. Signs on t-values indicate direction of relationship (e.g. switching to extra-nest activity was less likely with increasing corpulence).

model	predictor	t-value	d.f.	p
switch to extra-nest activity	corpulence	−3.23	236	<0.01
	age cohort	0.93	236	0.35
	spatial fidelity	0.96	236	0.34
	previous intra-nest activity	−0.58	236	0.57
	previous extra-nest activity	0.64	236	0.52
switch to tending extra brood	corpulence	−0.48	119	0.63
	age cohort	0.61	119	0.54
	spatial fidelity	1.30	119	0.19
	previous intra-nest activity	1.55	119	0.13
	previous extra-nest activity	−0.08	119	0.93
switch to transporting extra brood	corpulence	−4.43	165	<0.001
	age cohort	1.27	165	0.21
	spatial fidelity	−0.52	165	0.60
	previous intra-nest activity	4.19	165	<0.001
	previous extra-nest activity	−1.59	165	0.11