Saskatchewan

'Exciting and surprising': 23-million-year-old mammalian bones found at dig site in Sask.

Danielle Fraser said they've found bones of large and dog-sized horses, a cat tooth from one that was about the size of a cougar and rhinoceros tusk so far.

Danielle Fraser said they've found horse bones, a cat tooth, and rhinoceros tusk so far

Technician Margaret Currie and student Matthew Brenning digging for fossils in Grasslands National Park. The scientist team is made up of two graduated scientists lead by Danielle Fraser and two students. (Danielle Fraser)

A new site in Grasslands National Park is yielding fossils of 23-million-year-old relatives of modern-day horses, cats and rhinos.

The remote area in the park`s East Block was previously unknown to have mammalian fossils of these types. A survey in the Summer of 2017 showed fossils of horse bones and pieces of rhinoceros tusk. Now, the scientists from the Canadian Museum in Ottawa are back for more.

"On a day-to-day basis we are hiking out to our site, we're digging quarries and hoping to find bones coming out of the rock," lead scientists Danielle Fraser said.

The fossils are from 23 million years ago in the Miocene Era. For context, dinosaurs became extinct around 65 million years ago.

"It's really exciting and surprising to find them in Canada in part because the glaciations that happened during the last ice age pretty much scraped everything off of that age," Fraser said. "And so these types of rocks are really rare in Canada."

Fraser said these fossils have only been found in Saskatchewan, Alberta and Devon island in the Arctic.

The species can be identified by their teeth.

"We've discovered at least three species of fossil horse. One of them was about the size of a medium-size dog," Fraser said.

Field student Brigid Christison found a tooth from a carnivore that would have been around 23 million years ago in the Miocene Era. (Danielle Fraser/Twitter)

"We were very excited to find a fossil of a cat that would have been close to the size of a cougar," Fraser said. "We also found a mysterious jaw, that we're not sure. It's not a mammal."

Southern Saskatchewan was very different when these animals lived. Fraser said the Grasslands area would have had been warmer, rainier and had a lot more trees.

Fraser said there was a drying trend between the Miocene Era and modern day which drove the change to the grasslands in North America.

"We probably will be back next year," Fraser said. "We're going to look for small mammals like rabbits and rodents and if we find stuff in those rocks we will definitely be back and it could represent five to 10 years of work."

Danielle Fraser at a site in Grasslands National Park during the initial survey in 2017. (Submitted by Dan Smythe, Canadian Museum of Nature)

With files from CBC Saskatchewan's Morning Edition.