Data from: Bite of the cats: relationships between functional integration and mechanical performance as revealed by mandible geometry

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 dataset of extant and
extinct cat-like species to test for evolutionary transformations in size,
shape and mechanical performance, i.e. von Mises stress and surface
traction, of the mandible. Size and shape were both quantified by means of
Geometric Morphometrics while mechanical performance was assessed applying
Finite Element Models to two dimensional geometry of the mandible.
Additionally, we present the first almost complete composite phylogeny of
cat-like carnivorans for which well-preserved fossil 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 if 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.