Table 1. Independent contrasts results.

	Structures compared	Slope	95% CI	No. of contrasts
Primates	Frontal neog vs. rest of neog	1.18	1.06-1.30	24
	Frontal neog vs. subcort brain	1.38	1.22-1.53	24
	Rest of neog vs. subcort brain	1.13	0.98-1.28	24
	Total neog vs. subcort brain	1.10	1.01-1.18	37
Carnivores	Frontal neog vs. rest of neog	0.94	0.82-1.07	14
	Frontal neog vs. subcort brain	1.13	0.98-1.27	14
	Rest of neog vs. subcort brain	1.17	1.03-1.31	14
	Total neog vs. subcort brain	1.14	1.02-1.26	14
All mammals	Total neog vs. subcort brain	1.17	1.11-1.24	93

Slopes and 95% confidence intervals (CI) for regression through the origin of independent contrasts of frontal cortex gray matter (neog), rest of cortex gray matter, and subcortical (subcort) brain. Data for all mammals and for primate total neocortex consists of our own data combined with that of Frahm et al. (1).