A fossil of blood is found in a dinosaur

A study has found red blood cells in trace fossils of a dinosaur of the species Aratasaurus museunacionali, preserved in the National Museum of Brazil. Inside these cells were also traces of heme, the component of hemoglobin responsible for transporting oxygen. According to the authors, these would be the oldest traces of this molecule ever found.

“He discovered many oval structures of about 23 mm that had been transformed into minerals, within which iron, carbon and nitrogen were identified.”

This fossil was found in the Brazilian state of Ceará in 2008. They correspond to a young individual who lived 115 million years ago and is estimated to have a length of about 3 m. The fossil survived the fire at the National Museum of Brazil in 2018, after which Aratasaurus, which means “reptile born of flames,” was named.

It is a particularly curious finding, since when an animal dies, blood is one of the first elements that disintegrate. The researchers examined the internal channels of the bones through which the blood vessels pass under an electron microscope. In these interstices, he discovered a large number of oval structures of about 23 mm, transformed into minerals, within which iron, carbon and nitrogen were identified as components of the heme group.

The authors believe that after the death of the dinosaur, it was covered with bacteria, which created an oxygen-free environment. It has been suggested that, in the absence of oxygen, the decomposition of the corpse was slowed down or discontinued, and finally a manganese mineral retained the cells.