English: From source (under CC-BY): "Reconstruction of the head of Homotheriumillustratingthe process of the Canine Shear-Bite as hypothesised by Aker-sten (1985) for the genus Smilodon. First (A), the predator opensits jaws at full gape to encompass a chunk of skin and flesh on aconvex area of the prey’s body. At such a wide gape, the adduc-tor muscles of the mandible such as the temporalisand masseter,are too stretched to exert enough force for initiating a strong clo-sure of the jaws. In the next stage (B), the whole head is ventrallyflexed around the atlanto-cranial articulation using the force of theanterior neck musculature, while the front of the mandible, in con-tact with the prey’s body, acts as an anchor. This motion allowsthe initial penetration of the canine tips into the flesh of the prey.In the next stage (C), the upper canines sink deep enough todecrease the gape of the jaws to an angle where the adductormuscles can exert their full force and produce a deeper bite. Atthis point it is feasible that the machairodont pulled back its wholehead, tearing a large chunk of flesh from the prey. However, this pull is not a necessary condition for the effectiveness of the killingbite (Artwork by M. Antón).