A team of palaeontologists at the University College Cork (UCC) in Ireland, led by Daniel Falk and Prof. Maria McNamara, has solved a century-old mystery concerning the preservation of the fleshy parts of some fossil frogs. By studying 45-million-year-old fossil frogs from the Geiseltal site in central Germany, the researchers discovered that the excellent condition of the fossils is due to the preservation of ancient skin remnants. The team used advanced techniques such as scanning electron microscopy, synchrotron-X-ray analyses, and infrared spectroscopy to examine the fossils, which were not available at the time of their discovery in the early twentieth century.
PhD researcher Daniel Falk noted that the quality of preservation of the fossil frog skin is remarkable, with even subcellular structures such as collagen fibres being preserved. The skin of the frogs is replicated in the mineral calcium phosphate, which has allowed it to survive for millions of years. The team was also able to determine the habitat of the fossil frogs based on the preserved skin, indicating that these frogs likely spent most of their time on land. This discovery is significant as it challenges previous scientific opinions that have persisted for almost a hundred years and suggests that frogs evolved adaptations for life on dry land over 45 million years ago.
Professor Maria McNamara emphasized that fossil soft tissues can reveal hidden information about the biology of animals, and in this case, the preservation of the frog skin in a similar way to other European fossil frogs sheds light on their evolutionary history. The research underscores the importance of re-evaluating historic fossil collections using modern techniques to uncover new insights. The study was conducted in collaboration with the Martin-Luther-University Halle-Wittenberg in Germany, the Natural History Museum Bamberg in Germany, and the University of Oxford in the UK, with funding from the Irish Research Council, the European Research Council, and the International Association of Sedimentologists.
The team’s findings have provided valuable insights into the evolution and adaptations of ancient frogs, showcasing the importance of studying historic fossil collections. The research has also highlighted the significance of using advanced techniques to re-examine old specimens and challenge existing scientific assumptions. By studying fossil frogs from the Geiseltal site in Germany, the researchers have demonstrated how the preservation of ancient skin remnants can offer clues about the habitat and behavior of prehistoric frogs, ultimately contributing to a better understanding of their evolutionary history.
Overall, the study represents a significant advancement in the field of palaeontology, offering new insights into the preservation and evolutionary adaptations of fossil frogs. The research not only sheds light on the biology of ancient animals but also serves as a testament to the importance of collaboration and the use of modern techniques to re-evaluate historic specimens. By overturning long-standing scientific opinions and revealing the unique adaptations of ancient frogs, the team at UCC has made a valuable contribution to our understanding of prehistoric life.
