RESULTS

The reconstructed tooth and jaw movements for one species of each of the four groups are shown in see Figure 3, Figure 4, Figure 5, and Figure 6. There are four views of the occluding teeth and jaw joint surfaces shown in each figure. For the same four species, anterior and lateral views of the movement of the protoconid tip during a single chewing cycle are illustrated in Figure 7. After initial tooth contact (IC), the occlusal path tends to be slightly concave towards the beginning of that phase and straighter at the end of the closing phase until centric occlusion (CO). In all species, the main carnassial blades are no longer in contact at centric occlusion; for all but Group 1, other tooth elements are in contact at the end of the closing phase. Table 1 shows that the degree of lateral movement during occlusion was greater for Groups 3 and 4 than the other two groups. However, there was no discernable trend in occlusal closing angle (Table 1).

The large attrition facets of Acinonyx and Crocuta are not planar – they tend to be slightly convex, with greater curvature towards the tips, particularly for the lower teeth.