115-million-year-old dinosaur blood cells found in Brazil

Scientists have discovered fossilised red blood cells and collagen amino acids in the leg bone of a 115-million-year-old dinosaur, marking the first confirmed finding of its kind. The international team published their results in PNAS on 2 November. Researchers from Australia, Japan, Brazil, and the US used microscopic and chemical analysis to verify the blood belonged to the dinosaur, ruling out contamination from fungi or microbes. They identified heme, a key oxygen-transporting molecule, and found fossilised blood canals inside the bone. The blood came from a theropod called Aratasaurus museunacionali, found in Brazil in 2008, preserved by a low-oxygen burial environment. The discovery challenges assumptions that biomolecules cannot survive deep time, offering new insights into ancient animal physiology.