Reports

Program No.18-022

Comparative morphology on lorisid limb structure relating to resistance against loadings

EGI, Naoko

26th September,2006 - 13th October,2006

Switzerland

Lorisids are characterized by a slow arboreal quadrupedal locomotion that lacks a flowing phrase. It has been suggested that the ground reaction force affecting on the limbs are relatively low during the lorisid walk while that the loadings from muscles to the limb bones are high due to the statical support of the body. However, there has been no agreement on adaptations of lorisid limb morphology to this loading condition. Acquisitions of morphological indicators of resistances against loadings require information on internal structure of limb bones in addition to external shapes. In this study, differences in limb bone morphology between lorisids and other small primates are examined based on microCT images, which are expected to provide more accurate information on the three dimensional structure than the ordinal biplanar x-ray methods. The CT data were collected at the Anthropological Institute and Museum, University of Zurich, where large primate collection is present and a micro CT has been set up for research purposes. The use of the micro CT was permitted by Prof. Zollikofer, and the operation of the CT data collection was assisted by his laboratory stuffs. Humeri and femora of 80 specimens of lorisids (Arctocebus, Loris, Perodicticus, and Nycticebus) and comparative species of small primates were examined. Two kinds of measurements, diaphyseal cross-sectional properties at mid-shaft as well as distal humeral and proximal femoral articular structures such as trabecular orientations and cortical bone volume, will be calibrated from the CT images

Irchel Campus, University of Zurich

Skeleton of lorisid (Arctocebus)

micro CT at the Anthropological Institute and Museum, University of Zurich

HOPE Project<>