Tardigrades are minuscule, eight-legged creatures that can withstand extreme conditions, including the vacuum of space. They kind of look like fat little caterpillar-bear hybrids, earning them the name "water bears." Motherboard interviewed Mike Shaw, a naturalist, about the mysterious creatures for their Spaced Out series. Because they are so unlike other species on Earth, one theory holds that they evolved elsewhere and somehow traveled here on "space debris." For more on the science and a pretty impressive animated GIF of a dancing polar bear, visit Motherboard. 

For more videos from our "Friday Fauna" series, visit the Atlantic Video channel. While we continue to ponder the possibility of life beyond our planet, Megan Garber's "Swabbing and Hoping: How NASA Keeps Germs From Colonizing Mars" explores the very real issue of making sure Earthlings (of any species) don't contaminate the rest of the universe.