info:eu-repo/semantics/article
Mandible morphology and diet of the South American extinct metatherian predators (Mammalia, Metatheria, Sparassodonta)
Fecha
2017-02Registro en:
Echarri, Sebastián; Ercoli, Marcos Darío; Chemisquy, Maria Amelia; Turazzini, Guillermo Fidel; Prevosti, Francisco Juan; Mandible morphology and diet of the South American extinct metatherian predators (Mammalia, Metatheria, Sparassodonta); Royal Society of Edinburgh; Earth and Environmental Science Transactions of the Royal Society of Edinburgh; 106; 4; 2-2017; 277-288
1755-6910
CONICET Digital
CONICET
Autor
Echarri, Sebastián
Ercoli, Marcos Darío
Chemisquy, Maria Amelia
Turazzini, Guillermo Fidel
Prevosti, Francisco Juan
Resumen
Sparassodonta is a diverse group of extinct metatherian predators that include forms with diets ranging from omnivores to hypercarnivores, including potential bone-crushers and sabre-Tooth specialised species. Most of the previous dietary studies on the group were based on qualitative approaches or dental morphometric indexes and/or bite force estimations. In this study, we explore the evolution of mandible shape and diet of Sparassodonta in a comparative phylogenetic framework, using geometric morphometric tools and allometric and discriminant analyses. We analysed the mandible shape of 142 extant species of marsupials and placental carnivores, and 15 fossil sparassodont species. We found that the relationship between shape and size of the mandible is strongly structured by phylogeny, where the more derived borhyaenoids tend to possess stronger and larger mandibles. Derived borhyaenoid sparassodonts and basal borhyaenoids were classified as hypercarnivores (with short and robust mandibular body). Hathliacynid were classified as mesocarnivores or as hypercarnivores, but with lower probabilities and less specialised morphologies (with a long and slender mandible). Although dental morphology suggests that most of the species of Sparassodonta would have been hypercarnivores, the robustness of the mandible seems to be informative regarding the prey size and degree of specialisation. The relationship between mandibular size and shape, and talonid/trigonid relative size, is strongly influenced by the phylogenetic legacy, suggesting that ecological factors could have influenced the evolution of the sparassodonts.