A broken T. rex rib preserved a record of healing
Scotty（SKOT-ee）
The name of the largest T. rex skeleton discovered.
mineralized blood vessels
Blood-vessel structures preserved as hard fossil material.
neutron imaging
A way to make pictures of the inside of an object using neutrons.
What the rib revealed
Scotty, the largest T. rex skeleton discovered, has given researchers a rare look inside a dinosaur injury. One rib was broken while Scotty was alive. Inside the fossil, scientists found a broad network of mineralized blood vessels. The evidence suggests the injury was still healing when Scotty died, about 66 million years ago.
Why the setting mattered
Soft tissues usually disappear before fossilization is complete. Blood vessels are especially fragile. In Scotty’s case, iron-rich blood entered the injured area after the break. New blood vessels formed as part of the healing process. Scotty then died in a salty marsh before the rib had fully healed. The marsh slowed decomposition and helped preserve the delicate network.
How scientists looked inside
The project began in 2020. Jerit Mitchell first used micro-CT, a noninvasive X-ray method, at the Canadian Light Source. Later, the team combined more X-ray techniques with microscopy. Those tools helped researchers study the injury and fossilized tissues at very small scales.
In April 2026, the team used neutron imaging at Oak Ridge National Laboratory in the United States. They worked with the MARS and VENUS instruments. Cold neutrons helped reveal soft-tissue signals in smaller samples. High-energy neutrons helped scientists study deep features in larger bones, including Scotty’s rib. The scans did not damage the fossil.
Why the finding matters
Neutrons and X-rays interact with materials in different ways. Neutrons are especially sensitive to hydrogen and other light elements. X-rays are effective at showing heavier elements and dense structures. Using both methods gave researchers complementary information. It also produced detailed three-dimensional views of a large fossil without cutting it open.
Most fossils show hard parts, such as bones. Scotty’s rib preserves evidence of what happened inside the body during healing. That makes it an unusual biological record, not just a record of bone shape. The work also suggests that museum collections may contain more hidden clues. New imaging methods could reveal them without harming valuable specimens.
What is confirmed, and what is not
The neutron scans confirmed earlier observations from X-ray work and added new image contrast. Together, the findings support the presence of a mineralized blood-vessel network and an injury that was not fully healed at death.
The report does not establish the exact date of the injury. It does not show how long healing took. It also cannot tell us whether this pattern was common among T. rex. One rib is evidence from one animal, not a complete picture of the species.
What comes next
The researchers plan to keep analyzing the data from MARS and VENUS. They will study additional fossils and compare injury and healing patterns across species. They also hope to compare fossilized diseases and injuries with differences seen in modern species.
Scientists found healing clues inside a T. rex rib
📰 Full story: A broken T. rex rib preserved a record of healing
A broken dinosaur rib kept signs of blood vessels growing around an injury.
Scotty（SKOT-ee）
The name of the largest T. rex skeleton discovered.
neutrons
Very small particles that can show light elements inside objects.
salty marsh
A wet place with salty water where Scotty died.
💡 The gist
- Scotty had a broken rib 66 million years ago.
- Blood vessels formed as the injury started healing.
- Scientists saw the clues without damaging the fossil.
Scotty, the largest T. rex skeleton discovered, had a broken rib. Researchers found signs that the injury was healing. They saw a network of blood vessels inside the fossil.
Blood vessels are tiny tubes that carry blood. After the rib broke, iron-rich blood entered the injured area. New blood vessels formed there. They helped the body repair the break.
Scotty died before the rib healed completely. The dinosaur died in a salty marsh. That marsh slowed decay. The slow decay helped preserve the delicate blood-vessel shapes.
Scientists used two kinds of scans. They used X-rays and neutrons. X-rays show dense parts, such as bone, very well. Neutrons can detect light elements, especially hydrogen. The two methods show different details.
Together, the scans made detailed three-dimensional pictures inside the rib. The scientists did not need to cut or break the fossil. This is important because soft tissues usually disappear during fossilization.
A fossil often tells us about bones. Scotty’s rib also kept clues about healing inside the body. That gives scientists a rare view of dinosaur biology.
The finding has limits. It does not tell us exactly when the injury happened. It does not tell us how long healing took. One rib also cannot represent every T. rex.
Researchers plan to study more fossils. They want to compare injuries and healing between species. They will also keep examining the new scan data.
A dinosaur bone kept a healing clue
📰 Full story: A broken T. rex rib preserved a record of healing
Scotty was a T. rex skeleton with a broken rib.
fossil
An old part of a living thing that stayed in rock.
neutrons
Tiny things scientists use to look inside objects.
Scotty had a broken rib.
Its body was trying to fix the break.
Tiny blood tubes grew near the hurt place. Blood tubes carry blood around the body.
Scotty died before the rib was all better. The rib later became a fossil.
Scientists looked inside without breaking it. They used X-rays and neutrons.
They found old shapes from the blood tubes. So, the rib kept a clue about healing.
Scientists do not know how long healing took. They will study more fossils.