Do me a favour right now and picture in your mind the toughest animal on earth whatever you think it is and now imagine what that animal would do in the most inhospitable environment that you can imagine so for example if you thought of a grizzly bear on top of Mount Everest being attacked by a swarm of silverback gorillas you would be wrong that is neither the toughest animal, nor is it the most inhospitable environment but I thank you for the visual image, that was a good one do you wanna what he toughest animal on earth
is? well voilà, there you have it my friends, it is the Tardigrade also called a water bear or a moss piglet because they're plump and waddly and they like to suck on moss and you may have noticed they're actually kinda cute they're what scientists call "Extremophiles" which means they don't give a crap about where they live the Tardigrades secret is that, when the environment gets to tough they just shrivel up and die for a while with the option of reviving when conditions improve and that is the weird thing about Tardigrades, they're so extravagantly tough like
for no real reason, they're just supposed to like waddle around on moss and suck up water that's their job and yet in their dormant state, they can withstand temperatures close to absolute zero and up to 300°F they can survive being exposed to 1000 times the radiation that would kill an elephant they can withstand pressures up to 6 times what you find in the deepest oceans on earth what, what is the point of that, there's no ways that that would be useful on earth and you had better believe, that we've been sending these little waddlers into
outer space because what is the most inhospitable environment? yes, it's space in fact, scientists think that Tardigrades may be the key to understanding how life began on earth back in 2007, NASA put a bunch of Tardigrades on the Space Shuttle then they opened up an air locked door and left them outside in the vacuum of space for 10 days being exposed to crazy amounts of UV radiation then they brought them back to earth and when they got there, the Tardigrades were like: What's up? they were happy and healthy and some of them laid Tardigrade eggs
and had little Tardigrade babies, that were completely normal and we keep doing it earlier this year on the very last mission of the Space Shuttle Endeavour we send some Tardigrades up and the European Space Agency send some Tardigrades into space as part of a mission called "Tardigrades in Space" uhm, which isn't clever until you realize that they shortened it to "TARDIS" so the question is: why do we keep shoving these adorable little beasts uhm into the vacuum of space it doesn't seem like a very nice thing to do well, one: because we want to understand
how Tardigrades work, just scientificly how they can possibly survive these intense, horrible, inhospitable environments and two: because we're interested in proving the Panspermia hypothesis that is right "Panspermia" a word I'm not going to make a joke about so imagine for a moment a meteorite slamming into our planet and this meteorite is so large, that it actually ejects pieces of the earth into outer space now imagine on those pieces of earth that got ejected into outer space, there are Tardigrades if that little organism could survive the vacuum of space long enough to then fall down onto
another planet it could seed that planet with life, if life can be transmitted in that way then it becomes much more likely, that life is a very very common thing in our universe Panspermia hypothesis has been around for a long time, but thanks to Tardigrades it's starting to look a lot more credible so we can already thank these beasts for being a great proof of concept for us bot of course they will never now, that we are so in their dept they're just going to keep walking around on mars, sucking water off and occasionally visiting
other planets I'm Hank Green, that was today's SciShow dose, we hope you learned something
