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OTTAWA – (AFP) – Plants entombed under ice in Canada’s far north for centuries have come back to life after exposure to air and sunlight, Canadian researchers have found.
University of Alberta researcher Catherine La Farge collected what she believed to be dead mosses (or bryophytes) from the foot of a retreating glacier in Sverdrup Pass on Ellesmere Island.
Carbon dating determined the plants were 400-600 years old and had been entombed during the Little Ice Age that occurred between 1550 and 1850.
La Farge was then able to revive the mosses in a lab, overturning a long-held assumption that plant remains exposed by retreating polar glaciers are all dead.
Previously, new plant growth in these areas was considered the result of rapid colonization by modern plants surrounding a glacier.
But La Farge showed the plants’ resilience in research published this week in the latest issue of the journal of the Proceedings of the National Academy of Sciences.
“We know that bryophytes can remain dormant for many years (for example, in deserts) and then are reactivated, but nobody expected them to rejuvenate after nearly 400 years beneath a glacier,” La Farge said in a statement.
In her lab, she ground up the plant materials and placed them in potting soils. Within weeks, green filaments began to sprout. Of the 24 samples seven showed growth, successfully regenerating from the original parent material.
Mosses are hardy, having been around for 400 million years. They evolved from sea algae, paving the way for other land plants.
Unlike most other plants, mosses reproduce by cloning their cells, La Farge said. “Any bryophyte cell can reprogram itself to initiate the development of an entire new plant. This is equivalent to stem cells in faunal systems.”