Dinosaur Blood Cells Found in 115-Million-Year-Old Fossil

Researchers have discovered what appear to be fossilized red blood cells in the bones of a dinosaur that died approximately 115 million years ago, a finding published in the Proceedings of the National Academy of Sciences. The structures were found in the hind leg of an Aratasaurus specimen from northeastern Brazil, with chemical analyses detecting heme, a component of hemoglobin. Lead author Kliti Grice of Curtin University called it a "world premiere," though the preservation mechanism remains unclear. Grice clarified the find is not a "vial of dinosaur blood" but rather a "mineral and molecular echo of long-past biology." She expressed no fear of recreating dinosaurs, though companies like Colossal Biosciences are working on resurrecting extinct species such as mammoths.