“Tough” takes on new meaning when it is used to describe the tardigrade.

This microscopic animal, also known as the water bear for its tubby appearance, can survive being frozen, boiled, exposed to extreme radiation and high pressures, being starved for several years and put into the vacuum of space for several days. It can even endure having its body completely dried out, a process called desiccation, by pulling its eight legs and head into its exoskeleton and forming a tiny ball.

“They can remain like that in a dry state for years, even decades, and when you put them back in water, they revive within hours,” said Thomas Boothby, a postdoctoral researcher from University of North Carolina at Chapel Hill. “They are running around again, they are eating, they are reproducing like nothing happened.”