Without water, a human can only survive for about 100 hours. But there’s a creature so resilient that it can go without it for decades. This 1-millimeter animal can survive both the hottest and coldest environments on earth, and can even withstand high levels of radiation. Are Tardigrades Dangerous? No, at least not to humans. Other micro-organisms in their environment should be on notice though; those claws aren't for show. While most tardigrades are herbivorous, not all of them are, and they will eat you if you are smaller than they are and you are within reach of their claws.
Thomas Boothby introduces us to the tardigrade, one of the toughest creatures on Earth.
"Water bears" is a colloquial name for tiny multicellular critters that have always delighted microscopists. They are properly called tardigrades ("slow walkers"), and with four pairs of stumpy legs and lumbering gait, they do look a little like a microscopic bear (an eight legged, microscopic bear, that is). Tardigrades live in more places on Earth than humans do, so practically any handful of water has a chance of containing some. The easiest way to find them and care for them, however, is to look in scraps of wet moss.