Discovery
HABITAT
Where they are found
SCIENTIFIC STUDY
Ability to Adapt
Characteristics
General Biology
Reproduction
Tardigrades are widely unknown, even to many biologist. At the same time they are the most unknown creatures on earth and also the most fascinating. Some people consider them to be the most incredible animals on earth. Measuring only 0.02 to 1.2mm in length they resemble bigger animals such as reptiles, dogs, pigs, and yes, even bears. They have been reported to exist virtually anywhere on earth. They can be found in hot springs, on top of the Himalayas, under 5 to 200m of layers of solid ice or more, and in ocean sediments. . As a matter of fact they can usually be found just one or two steps out of your front door. Their most typical homes are moss cushions. Water bears stretch the limits of survival in the natural world. Around 750 species are known and specimens have been found from the deep sea bed to the Himalayas and from the tropics to the poles.
Apparently, resent research shows tardigrades can resist 6000 atmospheric pressure. That’s nearly 6 times the pressure of the deepest ocean water. Tardigrades can survive temperatures as low as -272 which is colder than the atmosphere in outer space, or survive at -200 for more than 2 weeks. Other species of tardigrades can survive further punishment such as temperatures as high as 125 C, and others can survive major doses of x-rays more than 245 times greater than that which would kill a mammal or any other animal for that matter. They are the only animals that can survive having their photo taken in an scanning electron microscope which involves placing them in a vacuum and then bombarding them with electrons. Probably the most amazing thing about them is the fact that they can go into a stage called cryptobiosis. Cryptobiosis is the sate in which water bears can reversibly shut their metabolism and effectively isolate themselves from everything. This ability is truly a close death-like-state. water bears can decrease their metabolism to less than 0.01 percent of normal or be entirely unnoticed and the water amount in their body may decrease to less than 1 percent. Water bears have been revived from the state of cryptobiosis for more than one hundred years and shown signs of life. Through it experiments it has been shown that frozen water bears could survive for ever. It is unknown what their limits may be but what is known is that they are the toughest animals alive.
