A new study has revealed that palm trees once flourished in what is now subarctic Canada, offering new insights into ancient arctic climates.
The research, led by Peter Siver, a professor at Connecticut College, and published in the Annals of Botany, confirms that the region maintained warm temperatures year-round about 48 million years ago, even during months of winter darkness.
Siver’s colleagues from Canada and Poland also contributed to the study.
Scientists discovered the fossils by analyzing tiny silica structures from plants called phytoliths, found in ancient lakebed residues in Canada’s Northwest Territories.
These fossils were extracted from a fossil site in the territory called the Giraffe kimberlite pipe locality.
These fossils, along with the remains of warm-water species, suggest that the arctic was once ice-free and had a climate similar to today’s subtropics, according to the study.
“These findings give us a window into past greenhouse conditions and help refine models predicting future climate change,” Siver said.
Siver’s team also documented fossilized stegmata – unique linear arrays of phytoliths in palm leaves – marking the earliest known record of this evolutionary trait that occurred by the early Eocene, a warm era in Earth’s history that lasted about 34 to 56 million years ago.
The presence of warm-adapted aquatic organisms further supports the idea that this prehistoric arctic region was home to a lush, temperate ecosystem, the study said.
Researchers said the study challenges previous assumptions about when and where ice first formed in the Northern Hemisphere.
By looking at past environments, the study said scientists can better understand how ecosystems respond to long-term climate shifts.
