Saskatchewan researchers say they might have made a rare discovery related to dinosaurs, one that would be first of its kind in the world if confirmed.
Using the Canadian Light Source at the University of Saskatchewan, they have found a vast network of blood vessels preserved around a fracture in a rib fossil from Scotty the Tyrannosaurus rex.
“We were not looking for blood vessels, it was an accident,” said University of Regina physics Prof. Mauricio Barbi.
The preserved structure was found while Mitchell was creating an intricate, three-dimensional model of the 67-million-year-old fossil using data from the synchrotron scans, which use bright light to see inside objects at a molecular level.
“Actually, I had no idea what it was,” Mitchell said “As I am a physicist myself, I was really new to this project and new to paleontology … I just saw this interesting structure that was kind of weaving its way in between the normal bone structure.
“We have to find out what we can do next, what kind of analysis can we do to look into this deeper,” he said.
Mitchell emphasized they his team is cautious about the theories related to their findings, as it is too early to officially state and confirm findings from the project, which has been underway for more than a year.
Ottawa paleontologist Jordan Mallon was not involved with the study, but agrees the finding is “pretty cool.” The research scientist at the Canadian Museum of Nature says improvements in technology have really helped the evolution of paleontology.
We have to find out what we can do next, what kind of analysis can we do to look into this deeper.– Jerit Mitchell
“For centuries, it’s been thought that there’s effectively no trace of biological tissue in a fossil — that there shouldn’t be,” he said. “And yet, as we start to put these things under the microscope and look at them with new techniques, and look at them in more depth, it turns out the fossilization process isn’t quite as straight forward — or maybe not as rapid — as we thought it would be.”
While things such as preserved blood vessels and cells are a really rare find, Mallon said that it turns out, they do exist.
Scotty remains a marvel
Discovered in 1991 in Saskatchewan’s Frenchman River Valley, near Eastend, Sask., Scotty holds the distinction of being the largest T.rex skeleton ever found in the world.
A full-scale, approximately 15-metre tall replica of Scotty is displayed prominently in the Royal Saskatchewan Museum. The museum has the actual fossils in their care, as well.
Mitchell says they believe their findings relate to how the Scotty healed its injuries.
“One of our hypotheses is that this fracture might sort of be the cause of seeing this vascular structure,” he said. “So we don’t see this rampant vascular structure in another section of the bone. We only see it around where this fracture is.”
Mallon says potentially finding out how dinosaurs healed is notable, particularly in the case of Tyrannosaurus and its relatives, because life wasn’t easy for them.
“Their facial bones are frequently scarred, which tells us that probably at sexual maturity these things were biting one another’s faces, maybe for territory, maybe in sexual disputes,” he said.
“So, to know something about how they coped with… that lifestyle, would be interesting.”
The team plans to extrapolate its findings from Scotty’s rib to other fossils, particularly those with similar fractures. Barbi says he has contacted the Royal Tyrrell Museum in Drumheller, Alta., and submitted a proposal for the team through the Canadian Light Source.
“To test this hypothesis, we want to look into other bones with … similar pathological features and see if we can identify something that is also connected,” he said. “Then, if we’ve narrowed down similar features in fossils and structures, we can expand and compare other species of dinosaurs.”
The team is also investigating how those blood vessels came to be preserved, including the chemicals involved.
Mallon says the potential addition of this finding to the fossil record is interesting.
“The blood vessels that we find in animals commonly today, we’re finding back in the fossil record,” he said, adding that scientists can now trace modern body plans back hundreds of millions of years, because of this kind of research.
Similar discovery in Montana
A similar discovery was made in the United States in 2005. That’s when researcher Mary Higby Schweitzer of North Carolina State University recovered soft tissue, including what might be blood vessels and cells, from a Tyrannosaurus rex fossil found in Montana.
Her findings, with co-authors Jennifer Wittmeyer and John R. Horner, were published in the National Library for Medicine in 2006. Schweitzer dissolved away the mineralized portion of the fossil and was left with soft, stretchy tissue.
While the findings are similar, they are distinctly different, Barbi said.
“She found still pliable, soft structures in a small area, whereas we seem to have this structure – mineralized in our case – spread over a larger area,” he said, adding that combining the two findings means they could fill a gap in the study of evolution.
This isn’t Barbi’s first big dino discovery using the synchrotron.
In 2012, he was on a team in the Alberta Badlands that discovered preserved patches of dinosaur skin from a 72-million-year-old hadrosaur dinosaur.
Using the Canadian Light Source, the team was able to compare the skin of a dinosaur with modern animals, which found that the hadrosaur from the Late Cretaceous period in Alberta had skin that very closely resembles the skin of a modern crocodile.
“The importance is the preservation of the structures,” Barbi said. “I could see the nucleus of the cell.”