Tardigrades — also known as water bears or moss piglets — are microscopic lifeforms that live in some of the most extreme environments imaginable.
SEBASTIAN KAULITZKI/SCIENCE PHOTO LIBRARY/Science Photo Library/Getty Images
Tardigrades live in conditions so hostile to life as we know it, that they may offer a glimpse at how life could flourish on other planets.
Researchers from the U.S. and U.K. found tardigrades move their limbs in a way similar to insects, despite being many times smaller and living in different environments.
Tardigrades’ coordinated limb movements are unlike those of other microscopic lifeforms and make it possible to maneuver in their extreme habitats.
Most tardigrades live in or near freshwater, but they’ve also been found in ocean, mountain, and forest habitats, according to the Marine Biological Laboratory.
SCIEPRO/SCIENCE PHOTO LIBRARY/Science Photo Library/Getty Images
They can even survive in extremely high or low pressure, and from -328 degrees Fahrenheit to 300 degrees Fahrenheit.
Scientists from Japan found two tardigrades and an egg frozen in a more than 30-year-old moss sample from Antarctica.
After being thawed and rehydrated, one of the tardigrades gave birth to living offspring. The egg hatched, and the tardigrade that came out went on to have babies of its own.
The key to tardigrades’ resilience is their ability to enter a low metabolism state and curl into a ball called a tun.
STEVE GSCHMEISSNER/Science Photo Library/Getty Images
After the hours-long process of turning into a tun, tardigrades can survive in extreme conditions without food or water for decades.
Scientists from the University of Tokyo found a protein in tardigrades that protects their DNA from radiation damage.
VICTOR HABBICK VISIONS/Science Photo Library/Getty Images
That means they could feasibly survive space travel and suggests humans genetically engineered to make the same protein could one day be better suited for life in space.
The fact that tardigrades even have a complete digestive system is noteworthy, given how alien they seem otherwise.
NANOCLUSTERING/SCIENCE PHOTO LIBRARY/Science Photo Library/Getty Images
Scientists from Keio University in Tokyo found one species of tardigrade takes dumps almost as large as its body. Others only poop a few times in their lives, when they molt.
Researchers from Oxford University say tardigrades could survive every conceivable apocalyptic scenario until the end of the Earth itself.
Aleksandr Zubkov/Moment/Getty Images
To kill off tardigrades for good, all the water on Earth would have to boil away or the Sun would have to explode, the researchers say.
In 2020, an Israeli spacecraft crashed on the Moon, spilling its cargo. Included in that cargo were thousands of dehydrated tardigrades.
The problem here should be obvious: While tardigrades can survive in space, they would need a source of water to rehydrate. Last we checked, there’s none to be found on the Moon.
Robert Pickett/Corbis Documentary/Getty Images
Read more stories on animals here.