A groundbreaking study has shed new light on the preservation of biological molecules in fossilized dinosaur bones. Researchers from Curtin University, led by Dr. Kliti Grice, have found evidence of fossilized blood cells in 115-million-year-old dinosaur bones. The team analyzed the bones of Aratasaurus museunacionali, a theropod dinosaur discovered in northeastern Brazil. Using a combination of chemical extraction, Raman spectroscopy, and electron microscopy, they identified heme-related molecules and mapped supporting chemical signals to the microscopic structures within the bones' vascular canals. These structures, which resemble red blood cells, have retained chemical traces associated with blood for approximately 115 million years. The discovery strengthens the case for exceptional molecular preservation in fossilized bones and provides new insights into the biology of ancient organisms. The study, published in the Proceedings of the National Academy of Sciences, highlights the importance of combining molecular identification with detailed imaging to establish the biological origin of fossilized structures. While the discovery does not provide evidence of intact hemoglobin proteins or dinosaur DNA, it marks a significant step forward in understanding the preservation of biological molecules in fossils. The findings have implications for the field of paleontology and may shed new light on the evolution of life on Earth.