MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
A QUANTITATIVE APPROACH TO CRANIAL ONTOGENY OF THE PUMA
GIANNINI, N.; SEGURA, V.; GIANNINI, M.I.; FLORES D.
Lugar: Londres; Año: 2009
The cranial ontogeny of specialized mammals is relevant to the understanding of the connection of form and function in a developmental and evolutionary context. As specialized carnivores, felids are of especial interest. We studied the postnatal ontogeny of the skull in Puma concolor using a quantitative approach integrated with previous results of qualitative assessment of ontogenetic changes. We report patterns of multivariate allometry of 19 linear skull dimensions measured in 48 Argentine specimens of puma. We examined the (jackknife resampled) departures from isometry as well as the interplay of isometric and allometric trends in shaping the puma skull. Both the qualitative and quantitative results indicate that the major ontogenetic changes are directly linked to cranial structures that support a developing masticatory apparatus and its associated masticatory and neck musculature, which are essential for the action of canines and carnassials during the killing bite and the slicing of flesh. Sexual differences suggest that hypo- and hyper-morphosis are key heterochronic processes in the development of the puma skull. We postulate that this is also the case with interspecific differences in the felid lineage, which is characterized by impressive size variation within a remarkably conservative shape variation.