New field of research: crystal traces in fossil leaves

Study by the University of Bonn proves for the first time that enigmatic microstructures originate from calcium oxalate. In living plants, calcium oxalate crystals can take on bizarre shapes under the microscope (from left: hornbeam, button mangrove, Australian nettle) © Madieh Malekhosseini / University of Bonn . In fossil leaves, puzzling structures are often visible under the microscope. Researchers at the University of Bonn have now been able to show for the first time that they originate from calcium oxalate crystals. On the one hand, their discovery facilitates the identification of the ancient plant remains. But it also provides answers to the question of how the ability to form such crystals arose and what function they presumably perform. The results have now been published in the journal Nature Scientific Reports.