Three palaeontology students from the University of Alberta have blown the dust off a 40-year-old falsity, 76 million years in the making.
Victoria Arbour, Michael Burns, and Robin Sissons were on a trip to Toronto’s Royal Ontario Museum to study armoured dinosaurs called anklyosaurs when they discovered more than they expected.
Originally discovered in southern Alberta by the late Canadian palaeontologist William Parks in 1924, anklyosaurs were an armadillo-like dinosaur about four metres long.
Parks concluded he had discovered a new species of anklyosaur that he named Dyoplosaurus, or double-armoured dinosaur. But in the 1970s, a new set of researchers came along and reclassified Park’s find as another anklyosaur species called Euoplocephalus.
That reclassification, according to Arbour and her two colleagues, was wrong.
“The differences are subtle so it’s not surprising that they were lumped together for a long time,” Arbour said.
The students felt there was enough evidence to support reclassifying the species yet again as Dyoplosaurus.
“What that does is it shows us there were actually more types of armoured dinosaurs living in Alberta than we thought for a very long time,” Arbour said. “It’s kind of like an old, new discovery.”
While it may be an old discovery to some, it’s still very exciting for a group of university students.
“We were definitely all very excited,” Arbour said. “It was great to able to work together as grad students because this was our first big collaborative paper.”
All three students were studying different parts of the dinosaur skeleton, and Sissons’ focus was on how the animal got around, looking closely at its foot and limb mechanics.
The toenail on the last digit was the main point of interest for Sissons, and they had quite a different shape to them than the Euoplocephalus.
“The differences had been pointed out by other researchers in the past, but never really considered significant,” Sissons said.
“It was only when we looked at them in conjunction with all the other aspects that it added up to make us suspect that this was a different animal, or the same animal it was originally thought to be.”
The students’ findings were published in the Journal of Vertebrae Palaeontology in December.
