Brian Resnick writes: Paul Bartels gets a rush every time he discovers a new species of tardigrade, the phylum of microscopic animals best known for being both strangely cute and able to survive the vacuum of space.

“The first paper I wrote describing a new species, there was a maternal-paternal feeling — like I just gave birth to this new thing,” he tells me on a phone call.

The rush comes, in part, because tardigrades are the most fascinating animals known to science, able to survive in just about every environment imaginable. “There are some ecosystems in the Antarctic called nunataks where the wind blows away snow and ice, exposing outcroppings of rocks, and the only things that live on them are lichens and tardigrades,” says Bartels, an invertebrate zoologist at Warren Wilson College in North Carolina.

Pick up a piece of moss, and you’ll find tardigrades. In the soil: tardigrades. The ocean: You get it. They live on every continent, in every climate, and in every latitude. Their extreme resilience has allowed them to conquer the entire planet.

And though biologists have known about tardigrades since the dawn of the microscope, they’re only just beginning to understand how these remarkable organisms are able to survive anywhere. [Continue reading…]