Table 2.

Partial correlation coefficients between life-history components of r_max (maximum reproductive period (MaxRP=max lifespan−age at first reproduction) and fertility) and (a) r_max or (b) brain mass, partialling out body mass and the other life-history variable. (Partial correlation coefficients (r) and their p-values for species-level data are given; significant values are shown in italics.)

		altricials		precocials
		r	p-value	r	p-value
(a) rmax
mammals	maxRP	0.018	0.783	−0.276	<0.0001
	fertility	0.765	<0.0001	0.918	<0.0001
birds	maxRP	−0.049	0.566	−0.034	0.704
	fertility	0.837	<0.0001	0.862	<0.0001
(b) brain mass
mammals	maxRP	0.281	<0.0001	0.044	0.482
	fertility	−0.189	0.003	−0.601	<0.0001
birds	maxRP	0.068	0.428	0.217	0.015
	fertility	0.120	0.158	−0.239	0.007