Now I know most of you probably have never heard of a water bear, but they are some of the toughest creatures on earth.
There are nearly 900 species of Water Bears and can be found nearly everywhere on earth. Water Bears can range in size from 0.05mm to 1.2mm in length. They can be found virtually every where on earth, and possibly even space. Yes, space. In 2007 Water Bears were sent into space and exposed to the vacuum of space without any protection against the pressure or radiation. They have been reported to be able to survive extreme temperatures, both hot and cold, extreme pressure, lack of oxygen, extreme radiation, deadly poisons, and a century without any food or water.
They are able to survive all of this by undergoing a process known as cryptobiosis or to use a smaller word,going into the “tun” state. Tun means indestructible and they are exactly that when they enter this state. They seem clumsy and maybe a little bit cute when you look at them under a microscope, like a newborn puppy learning to walk almost. But they are not to be underestimated by their cute stumbling – they can survive almost anything.
They can nearly stop all body functions and just sit there and do nothing until they are re-animated with some water. They have survived radiation that is a thousand times the lethal amount for human beings, temperatures as low as -328°F (-200°C) and as high as 304°F (151°C), six times the pressure of the deepest part of the ocean, and even being boiled in alcohol. They were recently revived from moss that is over a century old.
They are not considered extremofiles because they are not considered alive when they go into the tun state because all of it’s body functions are stopped. They are still amazing creatures and scientists are studying how they are able survive these conditions and how people may be able to one day survive like them to.