Three-dimensional cranial ontogeny in pantherines (Panthera leo, P. onca, P. pardus, P. tigris; Carnivora:, Felidae)

Abstract

The Panthera lineage is a monophyletic clade of felids, supported by both morphological and molecular evidence. The lineage includes large species with cranial similarity such as Panthera leo and P. tigris, and other with very different cranium such as P. pardus. The aim of our work was to study the cranial ontogeny of Pantherines, elucidating whether their cranial shape is a product of size or phylogeny, and to compare these findings with available information about other carnivores. We studied 370 specimens using geometric morphometrics technique in three dimensions. Panthera leo and P. tigris show similar ontogenetic trajectories, sharing adult crania with wider rostrum, shorter basicranium and vertical occipital plate. The cranial configuration of P. leo is a scaling version of P. tigris. P. pardus shows the most different cranial pattern, with adults having a rounded braincase and zygomatic arches less expanded than the rest, whereas P. onca occupies an intermediate place between these patterns. P. pardus is the species with the smallest birth weight and the lowest growth rate, reaching a final size and shape later than the remaining species. Adult shape morphology reflects no relation to phylogenetic placement of the species and it is probably related to Pantherine body size.