Tardigrades Can Survive in Space, But Can They Handle Climate Change?

Hypsibius dujardini, a species of tardigrade Willow Gabriel/Goldstein Lab/University of North Carolina/Wikimedia Commons

You may have heard the rumors: tardigrades are tough. Giving the honey badger a run for its money, the tardigrade or water bear has been reported to be practically impervious to freezing cold and scorching heat and radiation. Even their eggs, according to Wired, may be able to survive a trip to space.

But, as New Scientist reports, climate change may not, perhaps, be as easy for them to shrug off. Researchers at the University of Modena set out to study the effects of climate change on tardigrades, who, according to New Scientist, are plentiful in the Antarctic. They did this by collecting a group of Antarctic tardigrades and exposing them to ultraviolet radiation, rising temperatures and dehydration. The results were published in a recent study in the Journal of Experimental Biology.

No individual stressor seemed to be all that bad. Tardigrades did fine with ultraviolet radiation alone. Rising temperatures? No problem. Ditto dehydration. After all, according to the University of North Carolina, tardigrades have the special talent of entering the state of cryptobiosis. They can survive in a dried-out form, without water, for years on end. When reintroduced to water, perhaps not unlike one of those pills that expand into sponges, they come back to life. But, the combination of ultraviolet radiation and rising temperature wasn't so great for the tardigrades. Dehydrated tardigrades survived at an especially slow rate when exposed to that combination.

And the tardigrades that survived were not in great shape. As New Scientist writes, they had delays in reaching sexual maturity and laid fewer eggs over the course of their lives.

Still, it's worth keeping in mind that it's reportedly unclear how much ultraviolet radiation specifically will intensify over time. "Whether this tardigrade is more at risk than, say, apex predators such as penguin, or ecosystem keystones such as krill, is not clear," Mark Blaxter, who studies tardigrades among other organisms at the University of Edinburgh told New Scientist .

According to the Goldstein Lab at the University of North Carolina, there are over 700 species of tardigrade on land and in sea and freshwater. In a section on their fact sheet that asks the perennial question of conservation: "Who cares about them?" The partial answer, they write, is a "peculiar culture of amateur microscopists who appear to be obsessed with tardigrades." While enthusiasts and scientists may be the ones who care most, understanding how animals and organisms are affected by and may adapt to climate change seems like a worthy pursuit.