Episode 17: Do Invincible Creatures Exist?

Greenpeace USA
May 10, 2016 · 2 min read
Meet the tardigrade, the world’s most resilient creature. Photo by Dino Hristopoulos / Creative Commons.

Jessica Abel is a sci-fi writer who wants her work to be grounded in reality. The process of writing her next book — the forthcoming “Trish Trash: Rollergirl of Mars” — got her thinking about what outlandish and interesting factoids she can pull from creatures here on Earth.

Specifically, she wants to which animal (real animal, we’re not talking Superman here) comes closest to being indestructible. So we called up biologist Dr. Roberto Guidetti, who introduced us to the tardigrade, the world’s most resilient animal.

With the exception of being virtually invincible, tardigrades have little in common with the Man of Steel. For one, they’re less than one millimeter long, and can only be seen under a microscope. They’re so small that they don’t even have respiratory or circulatory systems — they don’t need them.

Affectionately called “water bears,” tardigrades are so resilient that fossil records show them outliving the dinosaurs. Gif via Reddit.

They can survive in an incredible range of extreme conditions, from the driest deserts to the highest mountains on the planet. According to Dr. Guidetti, they’ve even survived for brief periods of time in space.

Their “kryptonites,” it’s been discovered, are being physically crushed and the cosmic radiation of outer space. So, good luck with that.


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Completely Optional Knowledge

The podcast that answers questions you never knew you had. www.completelyoptionalknowledge.org

Greenpeace USA

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Campaigning for a green and peaceful future for more than 40 years — powered by people like you. www.greenpeace.org/usa

Completely Optional Knowledge

The podcast that answers questions you never knew you had. www.completelyoptionalknowledge.org

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