François Clarac

François defended his PhD in Paris under the supervision of Dr. Vivian de Buffrénil (Muséum National d’Histoire Naturelle) and Prof. Jorge Cubo (Sorbonne Université). The purpose of his PhD thesis was to decipher the potential adaptive role(s) of the dermal bone ornamentation in the evolution of the crocodylian lineage; a topic of investigation which is at the crossroad of various scientific fields: palaeontology, biomechanics, physiology and evolutionary biology. To fulfil objectives, François developed a multidisciplinary approach that was based on: 3D-bone modelling, finite element analyses, phylogenetic comparative analyses, histology, infrared thermography and ethology. The main outcome of the work was the discovery of the implication of the crocodylian dermal skeleton vascularisation in heat transfer: a function which turned out to be an adaptation to the ectothermic amphibious sit-and-wait lifestyle at the Triassic to Jurassic boundary (about 200 million years ago).

François then continued with two consecutive post-doctoral positions at Uppsala University in Sophie Sanchez’s team. The scope of these years of investigation was oriented toward the understanding of the water to land transition in the early tetrapods. The research was focused both on the early-tetrapod ecophysiological adaptations to land and on the bone mechanical changes which are related to the fin-to-limb transition. All the raw data were acquired via synchrotron scans which we obtained through beam time applications at the European Synchrotron Radiation Facility (Grenoble, France) in collaboration with Dr. Paul Tafforeau (ESRF) and Dr. Alexandra Quilhac (Sorbonne Université). After these synchrotron scan sessions, François modelled a large sample of extant and extinct vertebrate specimens in three dimensions. He then extracted and quantified the anatomical traits of interest in order to perform comparisons using phylogenetic comparative analyses and also developed a cutting-edge finite element method which revealed unprecedented results on the tetrapodomorph limb bones biomechanics.

François joined John Hutchinson’s Dawndinos ERC project on the 27th of September 2021 to determine the locomotion of early representative species of the crocodylian lineage such as the sphenosuchids. His contribution to this project will rely on a background in both the biomechanics of the limb bones and the evolution of the crocodylian lineage.

James Charles

James has a range of research interests including functional anatomy, biomechanical modelling, biplane radiography and medical imaging which have been put to use throughout his previous academic positions.

After receiving a BSc in Anatomy and Human Biology from the University of Liverpool and an MSc in Palaeoanthropology from the University of Sheffield, James completed his PhD at the Royal Veterinary College in 2016, working with John to develop, optimise and validate a novel musculoskeletal model and simulation of trotting locomotion in the mouse hindlimb. This work revealed interesting anatomical specialisations and functions within the mouse musculoskeletal system, which is largely under-studied given the heavy use of the mouse as a model species for many human neuromuscular disorders.

Wanting to combine these modelling skills with his interests in human functional anatomy, James then spent 18 months as a Postdoctoral Scholar at the University of Pittsburgh, where he worked to develop a framework for creating subject-specific human lower limb models. These bespoke models included individualised bones, muscle attachments and muscle properties from MRI and diffusion tensor imaging, as well as precise knee joint bone motions from biplane radiography. This work showed that more generic models are unlikely to truly replicate in vivo knee ligament dynamics, which highlights the need for personalised models in both clinical and non-clinical contexts.

Subsequently, James then moved back to the University of Liverpool for another Postdoctoral position, where he worked with Karl Bates, Kris D’Aout and Peter Falkingham to use this subject-specific modelling framework to predict intra-population variations in muscle dynamics and metabolic cost during walking over compliant and non-compliant surfaces. These data will inform how the morphologies of various hominin species within the fossil record are inferred in regards to their potential capabilities of bipedal walking over energetically expensive terrains.