Earth’s most indestructible being might be this wee barrel-bodied cutie with eight stumpy legs. Tardigrades are small, segmented animals with a penchant for water dwelling: lichens and mosses are their favored habitat. They’re found everywhere, from the deepest seas to the towering Himalayas, at the equator and polar caps. Their physical prowess lead some to suspect they come from outer space.
And they’ve been rocketed into orbit to test that theory. Well, more accurately, scientists were assessing their ability to survive extreme conditions, which might indicate how humans could adapt to the rigors of space.
In 2011, the European Space Agency sent tardigrades into orbit for twelve days on an unmanned spacecraft. The alien-looking critters with the sweetest nicknames (Moss Piglets, Water Bears) were affixed to the outside of the spaceship to stress their teeny torsos. Depending on the species (there are over a thousand), they can measure between 0.012 to 0.047 inches long.
Tardigrades are one of the most complex of all known polyextremophiles. This little animal normally waddles around on its plump little legs sucking juices out of mosses and lichens.
But when exposed to heat or cold or drought, they conjure up superpowers, retracting clawed legs and folding into a tight curl. Releasing 99% of their body water, they enter into suspended animation. In this cryptobiotic state, they can endure temperatures ranging from -328°F to +303°F. They can be exposed to radioactive material (a thousand times more than humans tolerate) and repair their own DNA.
This ability to turn off “life” for extended periods give them desert survival skills that make camels blush. It also means a tardigrade lifespan might be as short as six months, but could last a century. There’s a story of one found trapped in a museum’s 140-year-old moss specimen, brought back to life by simply adding water.
The puffy plant eaters are practically indestructible. Check out this brief video overview from naturalist Mike Shaw:
Says Shaw, “The tiny creatures lives fully in the here and now. He’s not thinking about the future, thinking of the past, just living in the present moment. If we could learn acceptance, we could all be a lot happier. I Know I’ve been alot happier since I’ve accepted and embraced life as it is.”
Water bears are my existential heroes.
Image from Nicole Ottawa & Oliver Meckes / Eye of Science / Science Source Images