Adaptive zones of feliforms and evolutionary regimes within terrestrial mammalian carnivores

Abstract

Terrestrial carnivores have repeatedly evolved similar ecomorphologies, yet the relationship between dental morphology and diet remains inconsistently predictive and seemingly at odds with this observation. Here we examine the presence of carnivore adaptive zones and this form/function mismatch using a total-evidence phylogeny of living and extinct feliforms, modelling the evolution of body mass and dental toolkit (relative blade length of the lower carnassial). We identify three adaptive zones within feliforms: (1) an ancestral cataract of carnivory, comprising small-bodied, ecologically flexible taxa with largely stochastic dental evolution; (2) the broad ecology cursor, associated with restricted forelimb dexterity and increased reliance on cranial prey processing; and (3) the soft-flesh specialist, defined by strong selection for slicing-dominated dentitions in hypercarnivores. Extending beyond feliforms, we propose a fourth zone, the versatile omnivore, representing a distinct adaptive zone of dietary and morphological flexibility at large size. Across these regimes, dental morphology receives strong selection only in hypercarnivores, resulting in reliable predictions of diet. In contrast, taxa with broader diets show stochastic dental evolution, leading to the frequent misclassification observed in recent studies. This framework reconciles longstanding links between morphology and ecology with their inconsistencies, providing a predictive model for terrestrial carnivore evolution. The relationship between the form and function of terrestrial carnivore dentition is inconsistent, despite repeated evolution of similar ecomorphologies. Here the authors compile a total-evidence phylogeny to identify three adaptive zones within feliforms and to show that reliable predictions of diet can only be made in hypercarnivores.