Identification, structure and occurrence of fossil melanin pigments

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In recent years, numerous studies have shaped our knowledge about fossil melanin pigments including controversially discussed reconstructions of the colours of fossil organisms such as marine reptiles and dinosaurs. However, only very few studies include reliable analytical chemical investigations of fossil melanins based on mass spectrometry. The project will initially develop a specific and sensitive mass spectrometric method for the proof of eumelanin and pheomelanin in fossil samples, allowing detection of the pigments in small samples of rare fossil organisms. In addition to fossil vertebrates, for the first time, fossil invertebrates will be systematically analyzed for whose melanins very few chemical analyses exist to date. In addition, a structural analysis of fossil melanins based on microcryoprobe nuclear magnetic resonance spectroscopy (NMR) and solid state NMR will be carried out. Important objectives of the project are to clarify if several fossil melanins discussed in the literature in fact can be identified as melanins based on a chemical characterization and how fossil melanins from various parts of the organisms like eyes, skin, hairs, feathers or protofeathers differ from each other. Overall, the investigation should provide fundamental insights into the fossil record of complex macromolecules as well as a solid basis for the evaluation of paleo-colour reconstructions.