Traces of red blood cells found in 115-million-year-old dinosaur fossil in Brazil
Researchers discovered chemical signatures of heme inside mineralised cell-shaped structures within the fossilised leg bones of an Aratasaurus museunacionali.
Scientists have discovered traces that resemble red blood cells and chemical hints of blood pigment in a 115-million-year-old dinosaur fossil from Brazil, according to The Times of India.
The fossil belongs to Aratasaurus museunacionali, a meat-eating dinosaur from the Early Cretaceous. A team led by Curtin University in Australia analysed fossilised leg bones, including the femur, tibia, and foot bones, which were recovered from a gypsum mine in Ceará in 2008.
Using Raman spectroscopy, electron microscopy, and mass spectrometry, the researchers identified tiny, oval structures within mineralised vascular canals. They found traces of heme, an iron-rich molecule found in hemoglobin, and traces linked to collagen inside these shapes.
Professor Kliti Grice of Curtin University described seeing a heme signature inside the cell-like fossils after 115 million years as stunning. Researchers suspect the animal died in an environment covered in microbial mats, which, combined with a lack of oxygen, may have slowed decomposition.
The team noted that minerals such as the manganese oxide hausmannite likely formed a protective shell around the cells. While the findings were published in the Proceedings of the National Academy of Sciences (PNAS), the researchers clarified they have not found dinosaur DNA.
Paleontologist Mary Schweitzer noted that the findings in the fossils do not match all the characteristics of bird or crocodile red blood cells, though she agreed the chemical evidence is compelling. Scientists are now conducting experiments using microbial mats to study these preservation processes.