Scans Show Largest T. Rex Died After Fight

The discovery was possible because of something very unusual. Fossil bones are common, but soft tissue almost never survives. It breaks down long before scientists can study it. One of Scotty's ribs, however, still held hardened traces of the tissue that once covered it. This material is very delicate, so the team needed to look inside the bone without cutting it. They chose neutron imaging, which sends tiny particles through an object to map what is inside. The scans created detailed 3D pictures that the team could study under high magnification. Mauricio Barbi, a physicist at the University of Regina, said the find was like winning the lottery, because the rib contains a huge network of hardened blood vessels never seen before in a fossil.

Those blood vessels gave the answer. After the rib cracked, new vessels grew around the break, the normal way a body repairs an injury. The repair was never finished, so the dinosaur probably died soon afterwards, in what was then a salt marsh. Jerit Mitchell, a physics doctoral student at Regina who leads the project, said many museums hold fossils that still keep their secrets. The team now wants to use the same method on other specimens to learn how prehistoric animals lived and died.