Comparative Analysis of 3-D Trabecular Bone Architecture: Applications to Locomotor Reconstruction in Fossil Primates

点击翻译按钮获取中文摘要

The principal goal of this project is to measure important features of trabecular bone -- the spongy tissue found inside the ends of the long bone of the skeleton. The investigators want to measure the variation of trabecular bone structure across primates in relation to body mass and locomotion and to determine the mechanical consequences of that variation using computational models. Trabecular bone, which is made up of a complex interconnected network of rods and plates, has received a significant amount of attention in studies of aging and bone loss due to osteoporosis, but comparatively little attention from physical anthropologists and comparative anatomists. Many factors such as behavior, body size, sex, genetics, and development may play important roles in determining the structure of trabecular bone in adult animals. This project will investigate some of these factors by looking at three important questions: (1) how does trabecular structure vary within and between primate species and what is the relationship of this variation to body size and sex? (2) does trabecular bone structure reflect locomotor behaviors and differential limb usage during locomotion (e.g., in leaping or arm swinging)? and (3) how do the elastic properties of trabecular bone vary across body size, locomotor mode, and limb element?High-resolution x-ray computed tomography will be used to collect data from the humerus and femur for a diverse sample of living and recently extinct primates ranging in size from mouse lemur to gorilla. Bone features such as volume, thickness, number, shape, interconnectedness, and orientation will be analyzed. Micromechanical finite element models will be used to calculate the elastic properties of the volumes by simulating experimental compression tests. Using the bone architectural properties and elastic constants, the relationships among body mass, bone structure and the calculated mechanical properties will be analyzed.The intellectual merits of this project include producing a better understanding of the role of physiological and behavioral factors on bone structure. It will not only broaden understanding of bone biology and bone structural variation, but will also produce the comparative data necessary to reconstruct the paleobiology of extinct primates.This project also represents a cross-disciplinary international collaboration between physical anthropologists at Penn State University and a biomechanical engineer at Eindhoven University of Technology in the Netherlands in which the varied expertise of the researchers will be used to answer questions about bone biology that have relevance to primate anatomy, functional morphology, bone biology, and human health. The broader impacts of the project include the production of a large comparative dataset that will be implemented into the anthropological curriculum and used to train undergraduate and graduate students in physical anthropology. Copies of the CT data also will be given to the curators of the lending museums to be archived for use by other scientists and potentially to be used for interactive computer-based museum exhibits. The results of this project will certainly have implications for understanding human skeletal disorders such as osteoporosis.