Under the microscope, these creatures look like gummy bears, swollen and soft like a sculpture by Jeff Koons. Do not be fooled by its nice appearance, you have before you a virtually indestructible being . When the sun dies to become a red giant and boil the oceans, something that will inevitably occur in billions of years, small tardigrades will be the only witnesses of the end of the world .
These tiny eight-legged beings, 0.5 mm long, also called water bears because of their appearance and their curious way of moving, have the qualities that, according to research published by the universities of Oxford and Harvard, The ultimate form of life on Earth. What’s more, scientists believe they could be here for up to 10 billion years, until the sun scorch them after the oceans disappear.
Although an asteroid such as the one that killed the dinosaurs 66 million years ago hits again against our planet, the tardigrades will not be unmoved. In fact, no known space body that can enter our orbit has enough strength to do away with them. In the same way, they could survive supernova or gamma ray blasts, too far to destroy the planet.
The reason is the extraordinary resistance of these organisms, found in the water of almost any place, be they mountains, seas, forests or polar regions. They can live up to 60 years and spend half of them without eating or drinking. In 2016, a Japanese research institute announced that it had been able to “resurrect” successfully a water bear that had spent 30 years frozen, a record. Apparently, these microanimals are able to enter into a state of cryptobiosis, a process by which they stop or reduce all their metabolic processes until environmental conditions return to normal. This dehydration capacity leaves them “dead” for years. That specimen “slept” less than 20 degrees below zero, and that for decades.
Survive in space
The tardigrades withstand extreme temperature conditions of between 150ºC and 272ºC below zero. In addition, they withstand the pressure of the depths of the oceans (1,200 atm at the bottom of the Marian Tanks) and the space vacuum (0 atm), not to mention radiation (5000-6200 Gy). In fact, it is the only animal that has survived in outer space, as demonstrated in an experiment in 2007 to see how the vacuum, the cold and the radiation of that impossible environment. When the specimens returned, they were not only in perfect condition, but some females laid their eggs and had healthy offspring. One of their secrets, according to another research from the University of Tokyo, is that they have a shield against X-rays,
The resistance of the tardigrades suggests to the scientists that life is harder than it seems, and that perhaps other similar organisms may be developing in other worlds where until now it seemed, but impossible, very complicated. “The history of Mars indicates that it once had an atmosphere that could have harbored life, though under extreme conditions. Agencies with radiation-tolerance and temperature tolerances to latexes could survive long-term below-ground under these conditions, “says Abraham Loeb, chair of the Department of Astronomy at Harvard University. Similarly, the underground oceans believed to exist in Europe, the moon of Jupiter, and Enceladus, satellite of Saturn,
Water bears, in short, are an example that life can cling to the most difficult conditions.