The Kid Should See This

An up-close look at tardigrades and their poop

It is surely the stuff of science fiction: An extraordinary being arrives on Earth that can withstand a tortuous array of conditions: boiling, freezing, tremendous atmospheric pressure, near total dehydration, and exposure to massive amounts of ionizing radiation. While many joke that “cockroaches would be the only thing to survive an extreme global nuclear war”, in fact, cockroaches would not. These creatures would. They are also the only life form known to be able to survive the near vacuum of space for extended periods.

This introduction from Today I Found Out describes the tardigrade, nicknamed water bears or moss piglets, a microscopic water-dwelling invertebrate with eight legs and extremely resilient bodies. The video above, paired with The Nutcracker Suite: VII. Les Mirlitons by the Royal Philharmonic Orchestra, was filmed by photographer Craig Smith. More from

In the contemporary taxonomy they are considered as one of the invertebrate Phyla (that means they are not insects, mites or crustaceans, they are just tardigrades). There are over a 1000 described species so far, however it is estimated that the total number of tardigrade species may exceed ten times as many…

One of the main reasons for which water bears are considered weird is their ability to survive in extreme conditions. When they are in the active stage (i.e. when they crawl around, eat and reproduce) they are no tougher than any other animal. However, when conditions worsen water bears can dry or freeze – this peculiar form of existence is called cryptobiosis (or anabiosis). When cryptobiotic, tardigrades look like they are dead – they don’t eat, don’t move, and don’t breath – in other words their metabolism is undetectable.

The current record for this cryptobiotic state: 30 years.

But despite this ability, we still have things in common with tardigrades. Harvard Department of Molecular and Cellular Biology PhD grad Tessa Montague shared a video of their lichen/algae poop, “so in technicolor it’s a bright green poop!” You can spot that in the video above, too.

Tardigradus means ‘slow walker’ in Latin. Read more about tardigrades at Today I Found Out and Wikipedia.

You can find and see tardigrades with your own microscope. Watch this video next: How do you find water bears (tardigrades) in the wild?

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