Figure 4. Morphospace of all upper and lower canine teeth measured in this study, showing shape variation in robustness, curvature and tip sharpness among diets. Principal components analysis (PCA) of the Procrustes coordinates, where principal component 1 (PC1) is correlated with robustness and explains 50.63% of the shape variation present, and PC2 is correlated with curvature and explains 16.91% of the shape variation present. A, H, show the variation present in terrestrial mammalian carnivores across diet groups. B–G, I–N, show differences in upper and lower canine teeth for key diets, as indicated by minimum convex hulls (upper canine convex hulls are depicted by a lighter shade of the family colour and lower canine convex hulls by a darker shade of the family colour). Diet groups represented are as follows: meat (B, I), meat/bone (C, J), generalist (D, K), invertebrate terrestrial (E, L), carrion/bone (F, M) and plant (G, N). In O–Q, the lower case letters denote significant differences and are based on phylogenetically corrected analyses (series of phylogenetic ANOVAs, followed by pairwise post hoc testing for significant differences among diet groups) of robustness (PC1; O), curvature (PC2; P) and canine tip sharpness (based on standardized cross-sectional areas; Fig. 2; Q).