Water bears? have you ever heard of this name? i doubt it. Even i heard it very recently. So apart from them , who do you think most toughest according to your knowledge. I probably think you would say "Humans" Some might go step further and say virus , bacteria. Well they certainly are. But in the event of a celestial catastrophe, they would be good as squeezed little mosquito. can you survive forget about 100C but at least earth heated up to 50C.
So who is the most unkillable creatures even survive a planetary destruction . They are called "Slow walking water bears" a microorganism that lives in wet places. They are living in every areas of the planet. When they live in normal time , they just like all the other animals. but when they feel danger they get change.
Magic start when they feel threatened this 1mm long 8 legged lazy boy use a process called "anhydrobiosis" which is to remove the water from its body. They curled up into a ball and remove all the water from their body. When the water released from the body they start to create new type of molecules. which fill his body for the lost water. In this state a water bear can stay in many harshest environments. It says it can survive up to 6 years without water and even can be much longer based on variations. They can withstand the coldness much as 1 Kelvin (Closest to absolute zero) for few minutes and can survive in more than 300C environments. It also have less to no effect from radiation or space vacuum.
So in this cases they can survive a huge gamma ray burst , Asteroid attack or even sun going supernova. Keep in mind though they can survive sometime but not forever. they will eventually break apart but a quick dangerous event can certainly survive as a water bear.
Scientist are currently doing lot of experiments on them to increase the survivability of man also. Which is giving us lot of good results. Hopefully humans also in future turn into water bears so that we will also have the same survivability as them
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