Evolution of the head of early cartilaginous fishes

The evolution of the head, jaws, and pharynx of vertebrates has been an intense focus of study over the last two centuries due to its important functional role as well as its implications for the evolutionary success of Vertebrata. We propose to target this part of the skeleton in two early shark-like fishes which have played an iconic part in these studies: Cladoselache and Acanthodes. Synchrotron propagation phase contrast radiation microtomography (PPC-µCT) will allow us to visualize the three-dimensional structure of the head, jaws, and branchial arches in uniquely well preserved specimens, providing unprecedented detailed information on the anatomy of the head of two of the earliest cartilaginous fishes.