Blood Traces Found in 115-Million-Year-Old Brazilian Dinosaur Bones

An international team has detected molecular traces linked to blood in the 115-million-year-old bones of a Brazilian dinosaur, Aratasaurus museunacionali, potentially offering new insights into dinosaur physiology. The researchers found heme B, an iron-containing component of hemoglobin, inside vascular channels of the fossil's leg bones using advanced chemical analysis. They argue the molecules are animal-derived, as surrounding rock showed different chemical signatures, and suggest early mineralization helped preserve them. The findings are debated, as paleontologist Mary Schweitzer questions whether the structures are definitively red blood cells. The study also found collagen-related amino acids, and researchers propose applying these techniques to museum specimens to uncover previously undetectable chemical remains.