First-Hand Experience : a Methodology for Exploring Bone Architecture Adaptation and Biomechanics in Human Hands and Zebrafish Models

Cancellous bone structure functionally adapts to loading forces. It has previously been proposed that evidence of behavioural activities, particularly manual behaviours, can be derived from analysis of the cancellous bone structure. However, a comprehensive method of analysis that combines a localised analysis of the bone structure with biomechanical data of specific activities does not yet exist. This work outlines such a method and tests it on pilot data from two distinct populations: an archaeological modern human population with known life histories, and a group of Neanderthal hand bones. Novel datasets are produced in this research. It is shown that the resulting new methodology can be applied to specific hand bones to compare biomechanical inferences to morphometric analyses with the potential for evaluating functional adaptation to certain manual activities. The biomechanical portion of this methodology is further developed in analog skeletal models (larval zebrafish lower jaws) to investigate the relationship between different types of loading and musculoskeletal development. We found that in these models, genetic mutations significantly affect normal biomechanical functions, with implications for joint morphology change, and that certain hypergravity levels affect the material properties and function of the skeletal structure.