A screening approach for selecting fossils for molecular analysis

This study investigates the presence of preserved biological remains in fossils, which could be particularly critical for future studies aimed at understanding the evolutionary history of extinct organisms. We focused on osteoderms from specimens of glipotodonts Panochthus tuberculatus and Glyptodon reticulatus from the Late Pleistocene of Argentina. Our approach involved sectioning the osteoderms and staining them with Coomassie Blue, a dye with high affinity for proteins. Additional staining techniques included Hematoxylin and eosin (H&E) and Masson's Trichrome Staining on histological sections of the same specimens. Sudan IV staining was also performed to verify the presence of lipids. These methods rapidly detected proteins and lipids and mapped their spatial distribution within the specimens, enabling the selection of samples for further molecular analyses. The findings highlight the potential of these methods to advance evolutionary research and improve our understanding of relationships among extinct species.