Carnassial

Carnassials are paired upper and lower teeth modified in such a way as to allow enlarged and often self-sharpening edges to pass by each other in a shearing manner.

This dental arrangement has been modified by adaptation over the past 60 million years for diets composed of meat, for crushing vegetation, or for the loss of the carnassial function altogether found in pinnipeds.

[2] Carnassial teeth are modified molars (and in the case of carnivorans premolars) which are adapted to allow for the shearing (rather than tearing) of flesh to permit the more efficient consumption of meat.

Mesonychids, for example, had no carnassial adaptations, and as a result, the blunt, rounded cusps on its molars had a much more difficult time reducing meat.

Eutriconodonts possess several speciations towards animalivory, and the larger forms such as Repenomamus, Gobiconodon and Jugulator probably fed on vertebrate prey.

[16] In modern carnivorans the carnassial teeth pairs are found on either side of the jaw and are composed of the fourth upper pre-molar and the first lower molar (P4/m1).

The inside of the fourth upper pre-molar closely passes by the outer surface of the first lower molar, thus allowing the sharp cusps of the carnassial teeth to slice through meat.

[20] The shape and size of sectorial teeth of different carnivorous animals vary depending on diet, illustrated by the comparisons of bear (Ursus) carnassials with those of a leopard (Panthera).

[22] Wear and cracking of the carnassial teeth in a wild carnivore (e.g. a wolf or lion) may result in the death of the individual due to starvation.