Tyrannosaur tracks bring life full circle for U of A grad student

It’s a homecoming 66 million years in the making for Scott Persons when returning to the site of his first dinosaur dig.
Scott Persons examines the Tyrannosaur tracks found at Glenrock, Wyoming. (Courtesy of Scott Persons)

It's a homecoming 66 million years in the making for Scott Persons. 

The PhD candidate at the University of Alberta had his passion come full circle in the little town of Glenrock, Wyoming with the study of Tyrannosaur tracks.

When Persons was 13, he visited the Paleon museum in Glenrock for his first ever dig. Sean Smith, the museum's curator at the time and remains so, led him on the excursion and showed him the tracks all those years ago. 

"At first, it looked like a prehistoric pothole," said Persons in a press release. "But soon, I could see the imprints of three big toes each with sharp claw tips. It was so cool my jaw dropped. 

"Then Sean pointed up slope, and there were two more!"
Scott Persons posing next to a fossil. (Courtesy of Scott Persons)

Persons, now a graduate student, has returned to the site to research those very tracks after reaching out to Smith to encourage a formal study.

They have now published an article regarding the find in the peer-reviewed journal Cretaceous Research about the incredibly rare find.

Persons obsession with dinosaurs began early.

According to his parents, he was around two when he started loving the creatures. It's a passion that has not ceased to this day.

When he was 13 his parents sent him to Glenrock to see if he was truly dedicated to the study or if it was just a passing phase.

"They had me digging and hauling rocks and debris, cleaning stuff," said Persons. "And they thought that maybe then I'd wise up and go on to pursue a more lucrative career.
Scott Persons has been enamored with dinosaurs since he was two and a half. (Courtesy of Scott Persons)

"But as it turns out that plan backfired and I wound up loving the work and loving the place."

Since then, Persons has found himself at the U of A as studying his passion in depth.

He says the very same reason that brought him to Glenrock brought him to Alberta, the promise of dinosaurs.  

Persons says that the findings are extremely rare because they fall in succession.

Single footprints left by Tyrannosaurs have been found previously, but Persons says that only one other set of tracks like this have ever been found. 

In fact, Persons says that finding anything left behind by a top predator of any era is in itself a rare thing. 

"This one is really cool because it is a Tyrannosaur," said Persons, "and Tyrannosaur, being the top predator of late Cretaceous North America were, naturally, very, very rare components of the ecosystem. 
One of the three Tyrannosaur tracks in Glenrock. (Courtesy Scott Persons)

"You can't have a whole bunch of predators. You can only support a few in the ecology. So finding footprints of Tyrannosaur is actually really, really rare."

As for what exact type of Tyrannosaur caused the tracks Persons isn't sure.

The prints are too small to be a full-grown Tyrannosaurus rex, so it may be a juvenile.

It also may be the tracks of a lesser-known tyrannosaur, the Nanotyrannus.

The tracks themselves follow a left-right-left pattern, which allow scientists to see the speed that the animal, regardless of species, was moving.

"They were just such beautiful tracks," Persons said. "The one track you can see the footprints and actually make out the individual fleshy pads that make up the toes." 

Apart from the scientific aspect, the experience with the Tyrannous tracks was a personal victory for Persons.

After discovering his passion under the hot Wyoming sun all those years ago, Persons was able to use his knowledge to help put Glenrock on the map. 

"Glenrock is very, very special to me because it's the place that I went on my very first dinosaur dig.

"But Glenrock really is a gem of a fossil location."


To encourage thoughtful and respectful conversations, first and last names will appear with each submission to CBC/Radio-Canada's online communities (except in children and youth-oriented communities). Pseudonyms will no longer be permitted.

By submitting a comment, you accept that CBC has the right to reproduce and publish that comment in whole or in part, in any manner CBC chooses. Please note that CBC does not endorse the opinions expressed in comments. Comments on this story are moderated according to our Submission Guidelines. Comments are welcome while open. We reserve the right to close comments at any time.