An international research team reports finding fossilized red blood cells and collagen amino acids in the limb bones of Aratasaurus museunacionali, a theropod dinosaur that lived around 115 million years ago. The remains came from Brazil’s Araripe Basin, and the findings were published in Proceedings of the National Academy of Sciences.
Earlier studies had described possible red blood cell-like structures in dinosaur fossils, but had not chemically confirmed molecules derived from hemoglobin inside the cells. The researchers say the preserved samples contain heme, a component of hemoglobin that carries oxygen, providing evidence of fossilized blood remains.
The team proposes that the cells were mineralized by hausmannite. This mineral may have helped preserve their structures and biomolecular components, including collagen amino acids, over geological time.
Aratasaurus museunacionali is the only known species in the extinct genus Aratasaurus. Its fossils date to between 115 and 110 million years ago and were reported in a scientific paper in 2020. The dinosaur is estimated to have reached up to three metres in length and weighed about 34 kilograms.
Sources: elDiario.es.