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Cat-like carnivorous mammals represent a relatively homogeneous group of species whose morphology appears constrained by exclusive adaptations for meat eating. We present the most comprehensive data set of extant and extinct cat-like species to test for evolutionary transformations in size, shape and mechanical performance, that is, von Mises stress and surface traction, of the mandible. Size and shape were both quantified by means of geometric morphometrics, whereas mechanical performance was assessed applying finite element models to 2D geometry of the mandible. Additionally, we present the first almost complete composite phylogeny of cat-like carnivorans for which well-preserved mandibles are known, including representatives of 35 extant and 59 extinct species of Felidae, Nimravidae, and Barbourofelidae. This phylogeny was used to test morphological differentiation, allometry, and covariation of mandible parts within and among clades. After taking phylogeny into account, we found that both allometry and mechanical variables exhibit a significant impact on mandible shape. We also tested whether mechanical performance was linked to morphological integration. Mechanical stress at the coronoid process is higher in sabertoothed cats than in any other clade. This is strongly related to the high degree of covariation within modules of sabertooths mandibles. We found significant correlation between integration at the clade level and per-clade averaged stress values, on both original data and by partialling out interclade allometry from shapes when calculating integration. This suggests a strong interaction between natural selection and the evolution of developmental and functional modules at the clade level.

A new species of Rhinocerotidae (Perissodactyla), 'Ceratotherium' advenientis sp. nov., from the late Miocene (8.1–7.2 Ma) locality of Cava Gentile, Calabria (Southern Italy), is described. 'Ceratotherium' advenientis displays morphological characters close to Rhinocerotina, in particular to dicerotines, and can be distinguished from the late Miocene elasmotheres, teleoceratines and aceratheres recorded in Eurasia and Africa. The new taxon clearly differs from the European latest Miocene species Dihoplus schleiermacheri, Dihoplus pikermiensis, 'Dihoplus' megarhinus and Ceratotherium neumayri, and from the African species Ceratotherium douariense, Ceratotherium? primaevum and Paradiceros mukirii. 'Ceratotherium' advenientis also differs from the Chinese dicerotine Diceros gansuensis and from the extant African species. The new taxon is characterized by peculiar features, in particular in the morphology and dimension of the neurocranial portion, and by having a nuchal crest wider than in the extant African rhinoceroses, C. neumayri, C. douariense, and European latest Miocene species. A cladistic analysis places 'Ceratotherium' advenientis in a polytomy with the extant Diceros bicornis, C. neumayri and a small clade composed by C. simum and C. antiquitatis. The African affinities of the new taxon support the Calabrian-Peloritan arc as a northern extension of the African continental shelf during the late Miocene. [ABSTRACT FROM AUTHOR]