These tiny creatures can withstand more than any other animal on the planet, and you can probably find some in your backyard. They are truly nature's greatest survivors.
These small, segmented animals were discovered by Johann August Ephraim Goeze, an aquatic zoologist, in 1773. Over 900 species of water bears have been found everywhere around the world - from the Himalayan mountains (at elevations of over 6000 meters) to deep ocean areas (4000 meters below sea level). They are most often discovered on mosses, lichens, and various types of sediments. An easy way to observe them is to soak a piece of moss in spring water.
The amazing thing about these tiny, 1mm creatures is just how resilient they are to about everything. You can put them in space, in hot sea vents, and freeze them - no matter what you do, they'll survive.
You see, Tardigrades can survive in:
Extreme cold (at -272 degrees Celsius for a couple of minutes, or at -200 degrees Celsius for days on end)
Extreme heat (being heated to 181 degrees Celsius for a couple of minutes)
Extreme radiation (easily surviving 5,700 grays of radiation. A gray is about as much radiation as 5,000 chest x-rays. 10-20 grays can easily kill a human and most animals.)
Extreme dehydration (A tardigrade can survive for a decade with no water)
In a vacuum (A water bear can survive in space!)
These tiny organisms can be found everywhere - in fact, there are probably hundreds just a few meters from where you are standing. They aren't as publicized as they should be, but these creatures are truly fascinating. It's amazing that these miniscule beings can survive for so long when others will die out.