Researchers have identified preserved blood vessels inside a fractured rib bone from Scotty, the largest Tyrannosaurus rex specimen ever found. The structures, revealed using synchrotron X-rays, formed during the dinosaur's partial healing process 66 million years ago. The findings, published in Scientific Reports, offer new insights into dinosaur physiology.
Scotty, housed at the Royal Saskatchewan Museum in Canada, lived a challenging life marked by multiple injuries. One rib shows a large fracture that had begun healing when the dinosaur died around 66 million years ago. During recovery, the body ramps up blood vessel activity to aid repair, and these vessels mineralized into iron-rich structures preserved within the fossil, Jerit L. Mitchell, a physics PhD candidate at the University of Regina, and colleagues report in Scientific Reports (2025; 15(1)). They reconstructed the network using 3D models from advanced imaging data. Synchrotron X-rays from particle accelerators allowed non-destructive analysis of the dense bone, overcoming limitations of standard CT scans. Chemical analysis confirmed two distinct layers in the vessels, reflecting complex preservation conditions. This technique revealed intricate details impossible with traditional methods. The discovery sheds light on how large predatory dinosaurs like T. rex healed from injuries. It provides a basis for comparing healing processes across dinosaurs and modern birds, their closest relatives. Bones with injury signs may prioritize future searches for soft tissues, Mitchell noted.