It has four toes, rather than the usual three. It is around one metre tall, small, like a carnival pony. And it has no horn.
Some 23 million years ago, the creature roamed the High Arctic, crossing between North America and Eurasia — a feat researchers previously thought impossible.
“It” is a recently discovered, extinct rhino. Epiatheracerium itjilik, the Arctic rhino, is the rhinoceros that could be rewriting evolutionary history.
The Canadian Museum of Nature described the rhino species in a paper published Oct. 28, in the Nature Ecology and Evolution journal.
The lead author and head of paleobiology at the museum said that Arctic is filling gaps in understanding when it comes to evolution and biodiversity.
“We typically think of the tropics … we think of rainforests full of thousands of species, being these really rich centres for biodiversity, and they are,” Danielle Fraser said, “But the more we’re discovering in the Arctic, the more it’s clear that the Arctic played a very, very key role.”
This “key role” is helping us understand how and when rhinos crossed the North Atlantic to Europe and Asia.
Before this study, most paleontologists agreed that animals and plants could cross via the North Atlantic land bridge until about 50 million years ago, Fraser said. The land bridge was where Greenland is now, connecting North America and Europe.
But the Arctic rhino that was discovered is 23 million years old — far younger. Similar species were also found in Eurasia, meaning the species has been found on both sides of the land bridge.
This points to the idea that the Arctic rhino crossed over the land between North America and Eurasia much more recently than what was originally thought, challenging the idea that the land bridge closed around 50 million years ago.
“It kind of changes the textbook. [It] changes the textbook on how animals were moving around the globe,” Fraser said.
A phylogeny is a representation of evolutionary history. It assumes that all organisms are related through a common ancestor and that they share genetic material.
The Arctic rhino fossils were found in the windy, treeless Arctic tundra on Devon Island, Nunavut.
The late Dr. Mary Dawson found the first fossil specimen in 1984. By 1986, Dawson had found well-preserved parts of the rhino’s jaw and skull. The fossils were brought to the museum around 2010, where Fraser worked on the project.
Devon Island is so remote that if an emergency evacuation were called, it could take up to 10 days to be reached, said Marisa Gilbert, the senior research assistant and paleobiologist at the museum.
Jarloo Kiguktak, fossil collector and an Inuit Elder, was hired by the museum as a field technician. He’s from Grise Fiord, the next town over, because no one lives in Devon Island.
Kiguktak and the Gri Inuit community helped the museum search for more fossils.
He was also responsible for the species name; in honour of the rhino’s Arctic and Inuit home, itjilik derives from the word “frosty” or “frost” in Inuktitut.
The collaboration was important in the rhino’s discovery, Gilbert said.
“He would pick up a bone and say, ‘this looks like a seal,’ ” Gilbert said about Kiguktak’s skill. “He was able to look at various things because he hunts there. He’s lived on land. He knew where to go. He could predict weather.”
The Arctic rhino is one of many organisms being discovered and researched in the Arctic by the museum, creating awareness and discussion, Gilbert said.
Polar amplification — the idea that temperatures in Arctic regions will rise by greater amounts than in others — and climate change could be creating an interest that the museum has invested in for a long time, Gilbert added.
“The more permafrost is melting, the more fossils are being pushed out by this thaw cycle. And so it’s best for us to get up there, get those fossils before they disappear forever,” Fraser said.
But “[the Arctic rhino fossils] don’t actually belong as a part of the national collection,” said Scott Rufolo, the curator of paleobiology at the Canadian Museum of Nature. Nunavut became an official territory in 1999 and any fossils found after 2001 belong to the territory as opposed to the Museum of Nature.
“I don’t have the right to make decisions in terms of whether it can be displayed or be loaned out for study or given or have researchers given access to that without proper coordination,” said Rufolo, who is responsible for managing the national collection, including the Arctic rhino.
The material is expected to return home to Nunavut once a museum complex is eventually built there.
Rufolo described the Arctic rhino as “a very charismatic specimen,” which helps connect past evolutionary events.
“When people realize there was a rhinoceros that lived up in the Arctic, that really triggers the imagination,” Rufolo said.
Since the fossils are type specimens, meaning the original of their kind, the Museum of Nature cannot display the actual fossils. Instead, it plans to create a 3-D printed replica, which the team hopes will be displayed for the public.
So far, most of the specimen has been scanned, and the research team is seeking funding to finish the model.
For the researchers, many things about the Arctic rhino are still a mystery, such as why it has four toes, shifting from the typical weight distribution of rhinos’ and similar species’ feet.
“I always think about … rhinos and tapers are always giving you the middle finger, because they’re always putting the weight right on that middle finger,” Fraser said. The Arctic rhino challenges this but there’s no answer why yet.
The lack of a horn is no surprise though, Fraser and Gilbert said.
The Arctic rhino’s flat nose bone is similar to the other species in its family and is common for rhinos of the past, Gilbert explained.
“For people who don’t study fossil rhinos, it challenges their view of what a defining feature of a rhino is,” Fraser said, “but if you work on rhinos, you know that there’s a lot of hornless rhinos out there.”
“It would have been just this cute, little fuzzy guy walking around,” Gilbert said.
