Plants frozen under a Greenland glacier hundreds of years ago are growing again, after rapidly melting glaciers expose them to sunlight and air.
Courtesy of the Catherine La Farge / Proceedings of the National Academies of Science
It's like something out of a zombie movie, or at least Encino Man: What was dead and frozen for hundreds of years suddenly sits up, shakes its head a few times, and goes about its business.
But this is real, and happening with mosses in Greenland. Once buried under thousands of tons of glacial ice, these mosses are green and growing again.
And not just one or two feisty stragglers: Dr. Catherine La Farge and colleagues from the University of Alberta found between 60 and 144 different species of moss that are spontaneously regrowing after centuries on ice.
Glaciers on Ellesmere Island, off the coast of Greenland, are rapidly retreating, like most glaciers around the world. As they pull back, they are uncovering whole ecosystems of mosses that are starting to wake up and blink in the sunlight.
Scientists saw the newly exposed mosses just a few feet from the edge of Teardrop Glacier on Ellesmere, on land that had been covered by the glacier only a year before. Most of the mosses were black, says La Farge, but they were structurally intact, and some looked suspiciously green.
"As I looked more closely I thought, 'Oh my gosh, what's this? Either this has somehow managed to retain a vestige of its original color, or it's just started to grow again after centuries under the ice,'" she told National Geographic. "The thought of that just blew my mind."
Arctic explorers have noticed these glacial-edge mosses before, but always assumed that they were seeing modern mosses that had blown onto the "dead mats," like squatters moving into a long-abandoned building. But when Dr. La Farge's team put the moss under a microscope, they saw that the green branches were growing from 500-year-old stems.
They put blackened moss with potting soil under a grow lamp and held their breath. Six weeks later, they had proof: these ancient mosses, frozen since the Middle Ages, were growing again.
These plants froze between 404 and 615 years ago, according to radiocarbon dating, or between 1398 and 1609, during the early part of the "Little Ice Age" that chilled much of Europe. The last time they saw the sun, English speakers were using words like "verily" and "forsooth."