Table 1.

Summary of regression model fits to observed palaeodiversity. ‘TJK’ is the simple biodiversity model; ‘DBC’ is dinosaur-bearing collections; ‘DBF’ is dinosaur-bearing formations. N = 26 stage-level time bins. Rows represent combinations of explanatory variables (‘models’, listed on the left), columns represent the coefficients of variables within the models (columns 2–7) and model fit parameters (columns 8–12). AICc is the version of the Akaike information criterion for small sample sizes [29]; R² is the generalized coefficient of determination ([30]; negative values are incurred when the model explains less variance than the null model).

	sampling (DBC or DBF)			biodiversity model (TJK)
	slope	t-value	p-value	slope	t-value	p-value	R2	log-likelihood	AICc	AICc (weight)
null model	—	—	—	—	—	—	—	−25.2	54.8	<0.001
TJK	—	—	—	0.08	0.34	0.7360	−0.033	−25.6	58.2	<0.001
DBC	0.761	5.21	>0.0001	—	—	—	0.422	−18.0	45.2	0.029
DBC + TJK	0.860	6.91	>0.0001	−1.07	−3.54	0.0018	0.603	−13.2	38.2	0.927
DBF	0.488	2.52	0.0186	—	—	—	0.156	−22.9	53.0	<0.001
DBF + TJK	1.370	4.97	0.0001	−1.22	−3.85	0.0008	0.457	−17.2	44.3	0.044