Two recent papers by Palaeobiology MSc students examine the biomechanics of different vertebrate fossils from Brazil.
The first study is by CJ Saclido along with an international team of co-authors and was published in the journal Palaeontology. CJ’s work investigates the feeding biomechanics of Brasilodon, a cynodont that is thought to be a close relative of the earliest mammaliaforms. The work, which came out of CJ’s Palaeobiology MSc project, shows that as Brasilodon grew its jaw became stronger and more resistant, suggesting that its diet may have changed as it became older. The research also shows that the jaw muscles of Brasilodon worked in a way that was more similar to other non-mammaliaform cynodonts than to early mammaliaforms.
The second study, published in the journal Proceedings of the Royal Society B by Ananth Srinivas and colleagues from Bristol, Hull and Brazil, addresses a long-standing hypothesis about the trade-offs between bite strength and aquatic adaptations in crocodiles and other aquatic predators that evolve from land-dwelling ancestors. The study was based on an examination of fossils taken from the Cretaceous sedimentary rocks of the Bauru Basin in Brazil, which preserves one of the most diverse and informative records of the evolutionary history of ‘crocodyliforms’ – the wider group that includes modern crocodilians and their extinct relatives. Three of the extinct species from the Bauru Basin were found to have dome-shaped (‘oreinirostral’) skulls. These were compared with three living species of modern crocodilians, which have broad, flattened (‘platyrostral’) skulls adapted for life in water. The findings show that the dome-shaped skulls of terrestrial ancestral crocodile relatives were much stronger and more efficient during feeding, when compared to the flatter skulls of modern semi-aquatic species. This suggests that modern crocodyliforms have traded strength for streamlining as they adapted to life in water.
Here are the details of the papers:
Salcido, C.J., Gill, P.G., Martinelli, A.G., Rawson, J.R.G., Corfe, I.J., Soares, M.B., Francischini, H., Schultz, C.L. and Rayfield, E.J. (2025), Functional morphology and biomechanics of an ontogenetic series of the Triassic cynodont Brasilodon quadrangliaris and bite performance in the sister taxon of Mammaliformes. Palaeontology 68, e70026. https://doi.org/10.1111/pala.70026.
Srinivas, A., Bright, J. A., Cunningham, J. A., Tavares, S. A. S., Ricardi-Branco, F., de Souza Carvalho, I., Iori, F. V., & Rayfield, E. J. (2025). Constraints and adaptations in crocodyliform skull evolution. Proceedings of the Royal Society B, 292, 20251773. https://doi.org/10.1098/rspb.2025.1773.