Tag Archives: Microbiology

Amusing Monday: Water bears live in fire and ice, maybe in your driveway

Plump little microscopic creatures, commonly called “water bears” or “moss piglets,” have gained a reputation as the most indestructible animals on Earth, with some species living in the cold Arctic and others living in flaming hot volcanoes.

New species of tardigrade, Macrobiotus shonaicus // Photo: Daniel Stec, PLOS One

They have been known to survive 30 years without food. Researchers have dehydrated them, frozen them, bombarded them with radiation and even sent them into the vacuum of space. While a few died along the way, a remarkable percentage have lived through extreme endurance trials and just kept on going.

I’m talking about a group of more than a thousand species known collectively as tardigrades, whose largest members are no bigger than a pinhead. Many are much smaller. These tiny lumbering little creatures with short appendages occupy the phylum Tardigrada, Latin for “tortoise-like movement.”

Amusing just by being themselves, tardigrades also have been featured in cartoons — including an entire episode of Southpark, in which science students teach them to dance to Taylor Swift songs and then do the Hokey Pokey before the little guys are accidentally turned into football fans destined to save the NFL.

More worthy of note is the real-life story of Kazuharu Arakawa, a researcher at Tokyo’s Kelo University who had been studying and reclassifying tardigrades in Japan using refined morphological criteria along with advanced DNA analysis.

On a whim, Kazuharu picked up a clump of moss that he found growing in a concrete parking lot near his apartment complex. He took the sample to his lab, placed it under a microscope and found viable tardigrades, supporting the notion that these creatures can live anywhere. Further study revealed that Kazuharu had discovered a new species of tardigrade, whose defining features include its eggs, which seem to reach out with tentacle-like appendages.

Egg of Macrobiotus shonaicus, showing filaments of varying lengths (scale: microns)
Photo: Daniel Stec, PLOS One

For confirmation, Kazuharu called on tardigradologists at Jagiellonian University in Poland. They eventually named the species Macrobiotus shonaicus and wrote up their technical findings, which were published last week in the journal Plos One.

The paper’s lead author, Daniel Stec, describes why the study of tardigrades is important to humanity in an interview with Tessa Gregory, of PLOS Research News:

“The most basic reason is human curiosity,” Daniel said, “and once you fall in love with tardigrades you only want to know more, especially since there is still so much to discover about them. However, there are also other reasons. Recently, tardigrades started to be used as model organisms in a variety of studies ranging from astrobiology, developmental and cell biology, physiology, evolutionary ecology and many other disciplines, in hope to address more general questions.”

The ability of a living creature to survive extremes could have useful applications on a human scale.

“Tardigrades became very famous in popular culture thanks not only to their undeniable cuteness, but mostly because of their ability to enter into cryptobiosis, a latent state in which virtually no metabolic activity can be detected. Yet, when dried or frozen tardigrades are provided with liquid water they come back to life as if nothing had ever happened,” he continued.

“This ability to withstand harsh conditions and to suspend their lives inspired researchers to produce dry vaccines that don’t require refrigeration or create transgenic human cells that are more resistant to irradiation. Who knows, maybe someday, thanks to tardigrades, we will be able to preserve organs for transplantation, extend our lifespan, or travel to other planets and stars, not worrying about detrimental effects of cosmic radiation.”

Stories about the new findings and other details about tardigrades:

Tardigrades are the subject of many amusing products, including T-shirts with the slogans:

You can even find tardi-games, like the one by Schell Games below.