Cranial function in a late Miocene Dinocrocuta gigantea (Mammalia: Carnivora) revealed by comparative finite element analysis

Carnivoran ecomorphologies evolved repeatedly during the Cenozoic. Whereas extreme forms (e.g. sabretoothed predators) probably represent similarities in ecology, other morphologies are more subtle with respect to the extent of their shared niche space. Finite element models of the skulls of Dinocrocuta gigantea, Canis lupus, and Crocuta crocuta were constructed to test the interpretation of D. gigantea as a bone cracker, an interpretation made on the basis of its large, conical premolars, and robust cranial morphology. Dinocrocuta gigantea is also of interest because it represents a lineage that has been placed in its own family, sister to Hyaenidae. Thus, functional similarity in craniodental performance could represent rapid convergence. The findings obtained indicate that the crania of D. gigantea and C. crocuta perform better in stress dissipation and distribution than that of C. lupus, regardless of P3 or P4 biting. In particular, the domed frontal region of the bone crackers received lower and more evenly distributed stress than C. lupus. Thus, the craniodental forms of the two bone-crackers are linked by functional advantage over that of C. lupus. Further examination of lineages such as borophagine canids could elucidate the extent of functional convergence of the bone-cracking ecomorph across diverse groups.