Possible dinosaur blood traces found in 115-million-year-old fossil, expert casts doubt
Researchers report microscopic structures and heme signatures in a dinosaur leg bone, but a paleontologist questions whether they are truly red blood cells.
Scientists say they have identified the oldest chemical evidence of blood-related material in a dinosaur fossil: microscopic structures resembling red blood cells and signatures of heme, a component of hemoglobin, in a 115-million-year-old dinosaur leg bone from Brazil. Mary Schweitzer, a molecular paleontologist, said the structures do not convincingly match the expected appearance of reptilian red blood cells.