RT Conference Proceedings
T1 The influence of skull shape modularity on internal skull structures: a 3D-Pilot study using bears
A1 Pérez-Ramos, Alejandro
A1 Martín-Serra, Alberto
A1 Pérez-Claros, Juan Antonio
A1 Schubert, Blaine W
A1 Pastor, Juan F.
A1 Figueirido-Castillo, Francisco Borja
K1 Cráneo
AB In order to capture the phenotypic variation of the internal skull structures, such asthe sinuses or the brain, it is necessary to perform CT scans in a large number ofspecimens, which is difficult and expensive. Therefore, while the external morphology ofthe mammalian cranium has been the subject of many morphometric studies, the internalstructures of the cranium have been comparatively less studied. Here, we explore how thevariation of external shape reflects the morphology of internal structures. We use thefamily Ursidae (Carnivora, Mammalia) as a case study because bears have a widevariability of cranial morphologies in part associated with different trophic ecologies. Todo this, we digitized a set of landmarks in 3D with a Microscribe G2X from the externalsurface of the cranium in a wide sample of bears. Additionally, the crania of seven bearspecies were CT-scanned and prepared digitally to visualize the 3D models of theexternal cranium morphology and of internal structures. Subsequently, we divided thelandmarks into two modules, splanchnocranium and neurocranium, and we perform atwo-block partial least squares analysis (2B PLS) to explore the intraspecific (static)morphological changes associated with the covariation between them. Thesemorphological changes were visualized using the morphing technique with the 3Dmodels, looking at both the external shape and the internal structures. In addition, weinferred the volume of the sinuses and of the brain in each hypothetical model. Ourresults show that the first two PLS axes are associated externally with changes in thebasicranial angle, face length and cranium height and width. Concerning the internalstructures, there are parallel changes in dorso-ventral and medio-lateral expansion ofsinuses and brain, accompanied by their corresponding changes in volume. In contrast,the third PLS axis is related to opposite changes in the volume of sinuses and brain.These preliminary results suggest that the opposite relationship between sinuses and brainvolumes in the bear cranium is not as evident as expected, at least at intraspecific level.
YR 2015
FD 2015-10-22
LK http://hdl.handle.net/10630/10567
UL http://hdl.handle.net/10630/10567
LA eng
NO Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026