I am a palaeobiologist interested in the evolution of major vertebrate groups. My research is rooted in understanding the anatomy and relationships of long-extinct animals, especially using computed tomographic methods to visualise fossils in 3D. I focus mainly on the evolution of sharks and rays, combining information from living sharks and rays with fossils to reach a better understanding of when and how major events in their evolution took place.
Palaeobiology, Evolution, Vertebrates, Sharks and Rays, X-ray computed tomography, Mesozoic, Palaeozoic, Phylogenetics, Comparative Anatomy
My postdoctoral work is funded by my Marie Skłodowska-Curie action, DEADSharks, in which I am trying to understand the evolution of sharks and rays in the Mesozoic.
Sharks and rays are an important and ancient group of animals, but their fossil record comprises mainly isolated teeth. I use computed tomographic methods to visualise the skeletal anatomy in the few rare body fossils, especially in the Cretaceous chalk of the UK. I aim to integrate this with anatomical and genomic information from the published literature and the collections of living sharks and rays here at Naturalis to reach a better understanding of the tempo and mode of their evolution. I am also interested in the earlier, Palaeozoic evolution of the group, as well as Palaeozoic vertebrates more broadly.
A selection of the topics I am working on currently:
- The anatomy of Mesozoic elasmobranchs
- Tempo and mode in elasmobranch evolution
- The anatomy of Palaeozoic chondrichthyans
- Feeding in Palaeozoic jawless stem-group gnathostomes
- The evolution of the head in the earliest gnathostomes
- Dearden, R.P., Herrel, A., and Pradel, A. (2023) Evidence for high-performance suction feeding in the Pennsylvanian stem-group holocephalan Iniopera PNAS
- Pradel, A., Dearden, R.P., Cuckovic, A., Mansuit, R.,and Janvier, P.J. (2021)The visceral skeleton and its relation to the head circulatory system of both a fossil, the Carboniferous Iniopera, and a modern, Callorhinchus milii holocephalan (Chondrichthyes). Ancient Fishes and their living relatives: a tribute to John G Maisey
- Dearden, R.P., den Blaauwen, J.L., Sansom, I.J., Burrow, C.J., Davidson, R., Newman, M.J., Ko, A., and Brazeau, M.D. (2021) A revision of Vernicomacanthus Miles with comments on the characters of stem-group chondrichthyans. Papers in Palaeontology
- Dearden, R.P., Mansuit, R., Cuckovic, A., Herrel, A., Dominique, D., Tafforeau, P., and Pradel, A. (2021) The morphology and evolution of chondrichthyan cranial muscles: a digital dissection of the elephantfish Callorhinchus milii and the catshark Scyliorhinus canicula. Journal of Anatomy
- Brazeau M.D., Giles, S., Dearden, R.P., Jerve, A., Ariunchimeg, Y.A., Zorig, E., Sansom, R., Guillerme, T., and Castiello, M. (2020) Endochondral bone in an Early Devonian ’placoderm’ from Mongolia. Nature Ecology and Evolution
- Dearden, R.P., Stockey, C.S., and Brazeau M.D. (2019) The pharynx of the stem-chondrichthyan Ptomacanthus and the early evolution of the gnathostome gill skeleton. Nature Communications 10, 2050