1Meet the Micro-Monsters
Tardigrades might be the coolest animals you have never seen with your own eyes! Often called 'water bears' because they walk with a slow, lumbering gait, or 'moss piglets' because of their cute snout-like faces, these tiny creatures are smaller than a grain of sand. You would need a microscope to spot one, as they usually measure only about 0.5 millimeters long. They have eight pudgy legs tipped with tiny claws and spend their days swimming through the thin films of water found on moss and lichen. Despite their adorable nicknames, they are the undisputed heavyweights of the animal kingdom when it comes to survival!
2Surviving the Impossible
What makes a tardigrade truly 'tough'? While most animals need very specific conditions to live, tardigrades can handle the most extreme environments in the universe. Scientists have discovered they can survive temperatures as low as minus 272 degrees Celsius—that is nearly absolute zero, the coldest temperature possible! On the flip side, they can also survive being boiled at 150 degrees Celsius. They have even been sent into the vacuum of outer space on a rocket ship and returned to Earth perfectly healthy, a feat that would be impossible for almost any other living creature.
3The Secret of the Tun
The secret to their 'invincibility' is a process called cryptobiosis. When a tardigrade’s environment dries up, it doesn't die. Instead, it pulls in its legs, loses 97% of its body water, and curls into a dry, crusty ball called a 'tun.' In this state, their metabolism—the engine that runs their body—slows down to almost zero. They can stay like this for 30 years or more! As soon as a single drop of water touches them, they soak it up like a sponge, uncurl their eight legs, and walk away as if they had just taken a quick nap.