Table 2. Exploration of body size distributions for major vertebrate groups, dinosaur clades, time periods and formations.

Comments	Category	Skewness	Location of modes on x-axis of body size distribution					Lilliefors D	p value
Major vertebrate groups	Dinosaurs	−0.758	6.3					0.105	<0.001
(see Figure 2)	Birds	0.837	1.3	4.6	5.2			0.091	<0.001
	Reptiles	1.077	0.9	6.1				0.109	<0.001
	Amphibians	1.140	0.0	2.8	4.2			0.082	<0.001
	Fish	0.180	−1.6	1.5	1.9	2.4		0.021	<0.001
	Extant Mammals	0.906	1.5	4.8				0.118	<0.001
	Pterosaurs	0.226	3.0	4.5				0.117	0.084
	Extinct Mammals	0.333	2.0	4.7				0.089	<0.001
Major dinosaur clades	Ornithischia	−0.909	6.1					0.157	<0.001
(see Figure 4)	Sauropodomorpha	−1.501	7.1					0.161	<0.001
	Theropoda	−0.305	5.3					0.084	0.076
Major time periods	Late Triassic	−0.432	4.3	5.6	6.4			0.195	0.029
(see Figure 5)	Early Jurassic	0.071	4.1					0.143	0.354
	Middle Jurassic	−1.369	6.6					0.182	0.015
	Late Jurassic	−1.294	2.3	6.0	7.2			0.142	0.008
	Early Cretaceous	−0.089	3.8	6.0				0.114	0.052
	Late Cretaceous	−0.950	2.3	3.6	4.7	5.7	6.5	0.119	<0.001
Major Formations	Morrison	−0.558	7.2					0.223	0.003
(see Figure 6)	Dinosaur Park	−0.697	4.2	6.5				0.170	0.070

Values are given for skewness of the distribution, location of modes in the distribution, Lilliefors D statistic and the p value showing significant difference from a normal distribution.