Canadian Arctic once home to vibrant forests, ancient fossils show

The High Arctic is known for frigid temperatures and treeless tundra but it was once home to lush forests carpeted with ferns, along with alligators, snakes, turtles, lemurs and birds, according to a new study.

While previous research has looked at mammal fossils from the area, this is the only comprehensive analysis of fossilized plants from the Canadian Arctic, the study says.

Researchers at the University of Saskatchewan looked at more than 5,000 plant fossils dating back to the Eocene epoch — around 56 million years ago — from Ellesmere and Axel Heiberg islands in Nunavut. 

"There were these rich forests living well above the Arctic Circle and that really drew me," said Christopher West, a paleobotanist and PhD graduate.

He said these ancient plants are related to modern trees like birch, alder, elm, sycamore and horse chestnut. They also found evidence of trees now only found in parts of eastern Asia like dawn redwood, Chinese swamp cypress and ginkgo. 

"The modernity of this particular forest was surprising in and of itself, but also that it had elements to it that we would not see today in North America," West said.

Wet temperate forests similar to those now found in B.C., were able to thrive in the Arctic as the climate was much warmer and wetter during the Eocene, West explained. The yearly average temperature was between 10 and 15 C, but the Arctic still experienced lots of sunlight in the summer and darkness in the winter, he said.

"That's a very stressful thing for an organism to endure, especially plants who are unable to move away," West said. 

He said the findings can help predict what the Arctic could look like as the climate rapidly warms — but we won't see a return to a forested polar region anytime soon.

West also noted although there have been cycles of climate change throughout geological history, the evidence is clear that current climate change is an anomaly.