‘The Arctic is a book of untold stories’

Ed Struzik -

In the summer of 1967, University of Calgary geologist Len Hills was at Ballast Brook on the north coast of Banks Island in the Arctic Archipelago, when he spotted a fossil protruding from the surface of the tundra.

It was cold, wet and snowing at the time. Hills picked up the specimen, put it in his bag and headed back to base camp not really knowing what he had found. He didn’t give it any more thought until Dale Russell, a paleontologist for the Canadian Museum of Nature, phoned him 15 years later and asked whether he had ever come across some Cretaceous-era bones during his explorations of the High Arctic.

Hills had explored nearly every island in the archipelago by then. But the call served to remind him of what he had found at Ballast Brook that day.

Back in his lab, Hills had a laugh when he gave the fossil a good wash. He could see then that it was the shinbone of a woolly mammoth, a giant elephant-like animal that lived in the Arctic long after the Cretaceous era ended and the last of the dinosaurs disappeared.

For some time, no one knew what to make of both this 22,000-year-old fossil and another one it that was found on Melville Island to the north. No one had thought that mammoths had lived beyond the north coast of Yukon and Alaska.

Five years ago, Dick Harington, another paleontologist with the Canadian Museum of Nature, offered an explanation that seemed to satisfy most everyone.

In an article published in the scientific journal Arctic, he suggested that Banks Island and parts of southwestern Melville Island were likely the eastern limit of Beringia. That verdant mass of lowland periodically connected Siberia to Arctic North America, when sea levels were much lower than they are today because most of the Earth’s water was locked up in glaciers.

Along with scimitar cats, short-faced bears, Ice Age horses and other now-extinct animals, woolly mammoths used to walk across this land bridge, before they were stopped by a massive sheet of ice that had expanded northward from the Keewatin region of Hudson Bay.

Even today, many scientists assume that much of Banks Island and other parts of the western Arctic Archipelago were largely ice-free through the last period of glaciation, and at least partially ice-free for hundreds of thousands of years before that.

You can almost see it in the soft, verdant look of this treeless tundra. There are 65,000 muskoxen — nearly two-thirds of the world’s population — living on this island. In many places, the terrain looks as if it was never scoured by the sharp edges and heavy weight of ice that expanded to its Ice Age maximum 18,000 years ago, before petering out 11,000 years later.

For most of his 40-year-long career working in the Arctic, University of Alberta scientist John England also thought that Banks Island was a relic of an ancient world. But some time in the 1990s, he and others saw something in the accumulation of geological evidence that suggested this theory was flawed.

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