Researchers in Canada have just made a pretty amazing discovery: they regrew 400-year-old frozen plants in their lab with little more than basic gardening skills. That’s fascinating news for researchers interested in understanding how plants recover from ice ages and glaciation, and it provides even more information for understanding our future on Earth. As if that wasn’t enough, those self-same plants could play an important role in space colonization, because they might have the resilience and flexibility needed to go beyond the final frontier.
First things first: these aren’t your ordinary garden-variety plants. They’re what are known as bryophytes, part of a large group of plants that lack vascular systems. Moss is probably the most famous of the bryophytes, and some of the plants in this study were mosses. Vascular plants like ornamental flowers, vegetables and other seeded plants have a complex system they use to suck up and distribute water and nutrients, and while some ancient specimens have been revived, it required pretty extensive work. Bryophytes are a little more low-tech, which serves to their advantage.
Scientists have always been aware that these plants are capable of enduring more extreme conditions than vascular plants. If they get dehydrated or frozen, they can revive once conditions get more favorable. This hardiness, scientists reasoned, explained how bryophytes survived ice ages and heavy glaciation; they must have lived near the boundaries of the ice, struggling to hold on until things warmed up.
However, that’s not actually what happened. As climate change has caused glaciers to recede worldwide, researchers are finding a plethora of new plant species and other fascinating things trapped beneath the ice, frozen in time. A team of Canadian researchers led by Catharine La Farge noted that as glaciers receded, mosses were growing in their wake. They weren’t the only ones, and they got curious about whether the mosses represented new growth taking advantage of the freshly-cleared ground, or revived ancient plants.
So they brought the samples back to the lab and took a look at them under their microscopes. What they found was amazing: the moss was producing fresh green growth, and when it was carbon-dated, it was clearly hundreds of years old. It hadn’t been able to live under the extreme cold and pressure of the glacier, but as soon as the ice receded, the plant started right back up again. Coming back from the dead would have allowed bryophytes to survive environmental catastrophes and keep growing when other plants couldn’t, explaining why these ancient plants have survived for so long.
As glaciers continue receding, the researchers warn, they’re going to keep exposing new plants. That doesn’t just mean that scientists will have more to study: it could also have a key environmental impact. As ancient species come back to life and the landscape changes, the balance of the environment may shift, and the direction of that shift is hard to predict.
The same durability and determination to live might mean that bryophytes ultimately outlive us on Earth, as they’ll be able to adapt to a variety of changing environments. While vascular plant species may die out in extreme conditions, these simple plants will keep de-differentiating, returning to a stem cell state and lying in wait for better times. This same property could be used to literally keep bryophytes on ice during space expeditions, allowing colonists and researchers to establish them on new worlds.