Adorable Tardigrades Have a Surprising, Fatal Weakness

By Stephanie Pappas - Live Science Contributor 4 days ago



(Image: © Shutterstock)

Tiny-but-tough tardigrades aren't as indestructible as previously believed.

These microanimals, which live in both fresh and salt water, are famous for their ability to survive extremes that would kill other organisms. But new research finds that the creatures rapidly wilt under heat. Water temperatures of less than 100 degrees Fahrenheit (37.8 degrees Celsius) can kill tardigrades in only a day. As global temperatures rise, that could become a problem for these animals, the authors of the new study said.

"Tardigrades are definitely not the almost-indestructible organism as advertised in so many popular science websites," said Ricardo C. Neves, a postdoctoral scientist in biology at the University of Copenhagen, who co-authored the new paper on tardigrade toughness, published Jan. 9 in the journal Scientific Reports.

The limits of tardigrades
Tardigrades are well-loved among science enthusiasts for their oddly adorable appearance. They have plump bodies and four sets of stubby legs. This cuteness has earned tardigrades the nicknames "water bears" and "moss piglets." Most species measure less than 0.02 inches (0.5 millimeters) in length.

They're also survivors. Tardigrades can handle being frozen, dried out, deprived of oxygen and blasted with radiation — they've even survived trips into the vacuum of space. The critters do this by going into what's called a "tun" state. They draw in their limbs and contract their bodies, suspending their metabolism and essentially entering a state of suspended animation. There may even be tardigrades in this tun state on the moon right now, after a crash landing by an Israeli lunar probe likely sent some specimens scattering.

More:
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