S5-3 Tue Jan 5 11:00 – 11:30 Testing the relationship of prehensile function and the musculo-skeletal morphology of chameleons using multi-body dynamics Luger, AM*; Watson, PJ; Dutel, H; Fagan, MJ; Herrel, A; Adriaens, D; Evolutionary Morphology of Vertebrates, Ghent University, Belgium; Medical and Biological Engineering Research Group, University of Hull, UK; School of Earth Sciences, University of Bristol, UK; Medical and Biological Engineering Research Group, University of Hull, UK; C.N.R.S./M.N.H.N., France; Evolutionary Morphology of Vertebrates, Ghent University, Belgium allison.luger@ugent.be
A prehensile tail represents an adaptation that has evolved in numerous vertebrate and invertebrate lineages. Prehensility is the ability to hold and grasp firmly an object, combining flexibility and strength. Yet, what it takes to make a tail prehensile remains poorly understood. In taking prehensile-tailed chameleons as a model organism, we aim to decipher the links between the variation in the musculo-skeletal anatomy of the tail and prehensile function. A previous study focused on the morphological variation in tail vertebrae of prehensile and non-prehensile chameleon species using µCT data. Following the detailed description of the tail musculature, we aimed at investigating how shape variation in the caudal vertebrae and muscle arrangement relates to grasping function. A prehensile tail is capable of withstanding high mechanical loadings and torsion, which we expected to be reflected in the musculo-skeletal morphology. Based on a 3D reconstruction of the tail vertebrae and musculature, we used Multibody Dynamics Analysis to investigate the effect of variation in vertebral shape and muscular arrangement on the efficiency of force generation in individual muscles. The results show that this variation has a large effect on the force output of the muscles. First results indicate that musculature associated with the proximal region of the tail are able to generate higher forces than those of the distal region, but further analyses are required to confirm this.