Fossilised red blood cells found in 115m-year-old dinosaur’s bone, say scientists

Scientists have discovered what appear to be fossilised red blood cells and traces of the molecule that gives blood its red colour in the bones of a 115-million-year-old dinosaur. The find, made after examining the leg bones of an Aratasaurus, a small meat-eating dinosaur from what is now north-eastern Brazil, has the potential to open up new avenues for research into dinosaur biology.

The round structures found in the bones resemble red blood cells and were confirmed by chemical tests that detected heme, essential for haemoglobin to transport oxygen. If the findings are confirmed, it could provide insights into dinosaur blood, metabolism and activity levels. However, the discovery is controversial, as biological tissues and molecules often degrade quickly, leaving little trace in ancient fossils.

The researchers are cautious, emphasizing that extraordinary claims require extraordinary evidence. If these structures are indeed fossilised red blood cells, it could indicate that deep time may preserve more molecular information than previously thought, opening up new possibilities for studying ancient organisms from museum collections.