Fossilized dinosaur blood cells reveal new clues about molecular preservation

An international team led by Curtin University has found the first unequivocal evidence of fossilized red blood cells and collagen amino acids in a 115-million-year-old dinosaur, reshaping understanding of fossil preservation. The discovery, published in Proceedings of the National Academy of Sciences, chemically confirmed hemoglobin-derived heme molecules inside red blood cells from the Brazilian theropod Aratasaurus museunacionali. The cells were mineralized with hausmannite, preserving them after rapid burial in a low-oxygen environment. Lead author Kliti Grice called the finding astonishing, challenging assumptions that biomolecules cannot survive deep time. Researchers say the work opens new avenues for molecular paleontology and could inform astrobiology, including the search for ancient life beyond Earth.