400-year-old plants, frozen during the Little Ice Age, and now uncovered by rising temperatures and melting glaciers, have been observed by researchers coming back to life — after centuries being frozen.
The plants — bryophytes — were found by a group of researchers from the University of Alberta who were out exploring a portion of Teardrop Glacier, high in the Canadian Arctic. The glaciers in the region have been melting at a rapid rate since around 2004 — receding about 3-4 meters every year since then. As a result of the melting glaciers, land is being exposed that has been covered in ice for hundreds of years — since the period of time that’s been dubbed the Little Ice Age, from about AD 1550 to AD 1850.
“We ended up walking along the edge of the glacier margin and we saw these huge populations coming out from underneath the glacier that seemed to have a greenish tint,” said Catherine La Farge, lead author of the study.
Samples of the 400-year-old bryophytes were then taken, and have since then been flourishing in the lab.
“When we looked at them in detail and brought them to the lab, I could see some of the stems actually had new growth of green lateral branches, and that said to me that these guys are regenerating in the field, and that blew my mind,” she stated in an interview with BBC News.
“If you think of ice sheets covering the landscape, we’ve always thought that plants have to come in from refugia around the margins of an ice system, never considering land plants as coming out from underneath a glacier.”
Bryophytes, while they are plants, are quite a bit different from the ones that you may be familiar with — they don’t have vascular tissue, which is part of what makes them so resilient with regards freezing and desiccation. They are capable of being completely dried out during long Arctic winters, only to begin growing again once the weather improves.
According to the researchers, the retreating glaciers are revealing more than just bryophytes though — an array of life, including cyanobacteria and green terrestrial algae, has been found there. And many of these species that are being found are completely new to science.
“It’s a whole world of what’s coming out from underneath the glaciers that really needs to be studied,” Dr La Farge said. “The glaciers are disappearing pretty fast – they’re going to expose all this terrestrial vegetation, and that’s going to have a big impact.”
The new research was published in the Proceedings of the National Academy of Sciences.