Scientists discover 115-million-year-old dinosaur blood traces in Brazil

An international team of researchers has identified mineralized red blood cells and chemical traces of heme within a 115-million-year-old dinosaur fossil. The discovery, published in the Proceedings of the National Academy of Sciences, involves the remains of Aratasaurus museunacionali, a meat-eating theropod dinosaur found in the Araripe Basin of northeastern Brazil.

While previous studies have identified structures resembling blood cells in fossils, this study provides the first definitive chemical confirmation of molecules derived from hemoglobin. Researchers detected heme, the iron-bearing molecule responsible for oxygen transport, alongside amino acids associated with collagen. The preservation was likely aided by rapid burial in an oxygen-poor environment and the presence of hausmannite, a manganese oxide mineral that acted as a protective shield around the cells.

Lead researcher Kliti Grice of Curtin University described the find as a landmark discovery that offers a molecular window into the physiology of extinct animals. The findings suggest that delicate biological molecules can survive much longer than previously believed under exceptional geochemical conditions.