For more than 66 million years, the bones of one of the most enormous predators ever to walk the Earth remained buried in rock.
Now, scientists have discovered something extraordinary hidden inside them: the mineralized remains of blood vessels.
The vessels were found inside Scotty, an exceptionally preserved Tyrannosaurus rex specimen housed at the Royal Saskatchewan Museum in Canada. Scotty is recognized as the largest known T. rex ever discovered and is also among the most complete.
The discovery offers an unusually intimate glimpse into dinosaur biology.
Most knowledge about dinosaurs comes from their fossilized bones and teeth. These hard tissues can reveal a great deal about anatomy, growth and behavior, but soft tissues are exceptionally rare. Preserved blood vessels, muscles, ligaments, skin and other delicate structures can provide information that bones alone cannot.
Researchers used powerful X-ray technology and advanced three-dimensional models to investigate the fossilized bone. Hidden within the mineralized material were structures consistent with ancient blood vessels.
The discovery began years earlier, when a physics undergraduate working with a research team studying fossils using particle accelerators noticed unusual structures in a T. rex bone. Further research eventually revealed what they may represent.
And the finding raises a fascinating question.
If delicate vascular structures can survive inside a dinosaur bone for tens of millions of years, what else could still be hiding within fossils that scientists have yet to detect?
There is still no confirmed dinosaur DNA recovered from fossils.
But discoveries like Scotty’s blood vessels show that the fossil record may preserve far more biological information than scientists once imagined.