Scientists have found Tardigrades is hot springs, on top of 20,000 ft peaks in the Himalayas, under sheets of ice in the arctic, underneath sand dunes in the Sahara, in the canopies of tropical rainforests, and embedded deep within ocean sediments. Tardigrades are probably living in your back yard. There are roughly 500 different species of Tardigrades, with the original Tardigrade having evolved over 530 million years ago. While the specific ecological purpose of these creatures is still unknown, they are resilient survivors and are capable of reversibly suspending their metabolism by undergoing a process called cryptobiosis where their water content drops to less than 1% of normal. Tardigrades are capable of emerging from cryptobiosis even after decades of metabolic inactivity. Imagine waking up after 20 years in a passive state state, and being able live your life and reproduce just as if nothing ever happened.
In addition to the magic of cryptobiosis, Tardigrades can survive in temperatures of over 300 C (cookie baking temperature) to temperatures under - 270 C (close to absolute zero when atoms stop vibrating), withstand the pressure of 6,000 atmospheres (nearly 6 times the pressure of water in the deepest part of the ocean - The Mariana Trench), survive 1,000 times the radiation exposure of other animals (including humans), and undergo chemobiosis in response to environmental toxins.
Tardigrades are also the first animals known to survive in SPACE and traveled on the last mission of the space shuttle Endeavor to be subjected to microgravity and cosmic radiation. Their survival legitimized the transpermia hypothesis, that life might have originated on another planet and traveled between planets as an embedded 'seed' on the surface of a meteorite.
I applaud the Tardigrade! All of the information that you would want to know about the Tardigrade can be found in the following chapters of an open source book written by Dr. Janice Glime of Michigan Technological University.
Just click on the pictures below to download the chapter.