Monday 30 January 2023

CANADA'S SMILODON

This fierce predator with the luxurious coat is Smilodon fatalis — a compact but robust killer that weighed in around 160 to 280 kg and was 1.5 - 2.2 metres long.

Smilodon is a genus of the extinct machairodont subfamily of the felids. It is one of the most famous prehistoric mammals and the best known saber-toothed cat. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats.

Up until a few years ago, all the great fossil specimens of this apex predator were found south of us in the United States. That was until some interesting bones from Medicine Hat, Alberta got a second look.

A few years ago, a fossil specimen caught the eye of researcher Ashley Reynolds as she was rummaging through the collections at the Royal Ontario Museum in Toronto. 

Back in the 1960s,  University of Toronto palaeontologist C.S. Churcher and his team had collected and donated more than 1,200 specimens from their many field seasons scouring the bluffs of the South Saskatchewan River near Medicine Hat, Alberta.

Churcher is a delightful storyteller and a palaeontologist with a keen eye. I had the very great pleasure of listening to many of his talks out at the University of British Columbia and a few Vancouver Paleontological Society meetings in the mid-2000s. 

"Rufus" was a thoroughly charming storyteller and shared many of his adventures from the field. 

He moved out to the West Coast for his retirement, first to Gabriola Island then to Victoria, but his keen love of the science kept him giving talks to enthralled listeners keen to hear about his survey of the Dakhleh Oasis in the Western Desert of Egypt, geomorphology, stratigraphy, recent biology, Pleistocene and Holocene lithic cultures, insights learned from Neolithic Islamic pottery to Roman settlements.

The specimens he had collected had been roughly sorted but never examined in detail. Reynolds, who was researching the growth patterns and life histories of extinct cats saw a familiar-looking bone from an ancient cat's right front paw. That tiny paw bone had reached through time and was positively identified as Canada's first Smilodon.

These Apex Predators used their exceptionally long upper canine teeth to hunt large mammals. 

Isotopes preserved in the bones of S. fatalis in the La Brea Tar Pits in California tell us that they liked to dine on bison (Bison antiquus) and camels (Camelops) along with deer and tapirs. Smilodon is thought to have killed its prey by holding it still with its forelimbs and biting it. And that was quite the bite!

Their razor-sharp incisors were arranged in an arch. Once they bit down, the teeth would hold their prey still and stabilize it while the canine bite was delivered — and what a bite that was. They could open their mouths a full 120 degrees.

Smilodon died out at the same time that most North and South American megafauna disappeared, about 10,000 years ago. Its reliance on large animals has been proposed as the cause of its extinction, along with climate change and competition with other species.