Now THIS is a tough little critter. These might be my new favorite animal, for sheer impressiveness.
(paraphrased/quoted from Wikipedia)
Tardigrades, commonly known as waterbears or moss piglets, are small, water-dwelling, segmented animals with eight legs. One of the most complex of all known extremophiles (organisms that can thrive in a physically or geochemically extreme condition that would be detrimental to most life on Earth), they’re incredibly hardy!
Waterbears can withstand temperatures from just above absolute zero to well above the boiling point of water. They can survive pressures greater than any found in the deepest ocean trenches and have lived through the vacuum of outer space. They can survive solar radiation, gamma radiation, ionic radiation — at doses hundreds of times higher than would kill a person. They can go without food or water for nearly 10 years, drying out to the point where they are 3% or less water, only to rehydrate, forage, and reproduce.
Can we say WOW?!