Last week, in commemoration of the harsh cold winter season, I wrote about an organism that could not only survive incredible temperature extremes but could also keep on ticking after nuclear warfare, unfathomable amounts of UV radiation, and even a zombie apocalypse. Endospore forming bacteria would win almost all survivalist battles. However, today I want to write about an animal that is another incredible example of doomsday survival and let you take your pick as to which organism is better suited to survive the end of the world. Who will win the epic showdown, endospore forming bacteria or the Tardigrade?!
The tardigrade has an epic nickname as well just to make things even more awesome, it is commonly referred to as the “water bear.” But don’t worry, it also has a sweet and endearing nickname to appease the ladies, the “moss piglet.” Tardigrades are part of the animal kingdom, but occupy a phylum known as “tardigrada.” There are over a thousand tardigrade species, but generally they all are short, stocky water-loving invertebrates with four pairs of legs and tiny claws at the end of each leg. So what makes the water bear a potential post-apocalyptic survivor? I have chosen to discuss a few of its survival skills below.
They already have an unbeatable resume: The microscopic, unassuming tardigrade has already survived 5 mass extinctions in Earth’s history. They have been spotted at the tops of high mountain ranges and at the bottom of the deepest oceans near mud volcanoes. Researchers say they can even survive temperature extremes of as low as minus 328 degrees Fahrenheit up to highs of 300 degrees Fahrenheit and can withstand up to 1000 times more radiation than other animals. Go ahead and tear up your application for that “survivor of terrestrial catastrophes” job application right now, the tardigrade will get the job hands down.
Step aside Inspector Gadget: If you thought Inspector Gadget had an amazing array tools at his disposal, then you need to check out the moss piglet’s adaptations. Tardigrades can undergo a state similar to hibernation called cryptobiosis. In cryptobiosis, their body forms into a dehydrated ball and begins to produce chemicals necessary to protect their vital organs while their bodies very nearly shut down completely. This cryptobiotic state has also shown to prevent the formation of ice crystals if they are exposed to extremely cold temperatures and to safeguard against high levels of radiation. When water becomes available once more, their bodies leave cryptobiosis and begin to function normally again.
Space is not the final frontier for the Water Bear: If Earth ever becomes inhabitable for any form of life, the water bear could drift out into space and still survive. Water bears have been known to survive pressures as high as 1200 times that of our Earth’s atmospheric pressure and pressures as low as those found deep in space. Once in cryptobiosis (they form that dehydrated ball known as a “tun.”), some tardigrades have even been brought back to life after being exposed to the actual pressures and intense radiation of outer space.
Not only are these animals cute and cuddly, but they are incredibly durable! What we can learn from these amazing creatures is endless. But which ultimate survivor is better, endospore forming bacteria or tardigrades? Cast your vote in the comments section below!
Science word of the week: Cryptobiosis–The ability to undergo a near death-like state to suspend their metabolism and maintain their bodily organs until water and nutrients become available. Tardigrades have been known to survive for up to five years in a cryptobiotic state!
For more information on tardigrades, check out these awesome websites which I used to gather some of my information for this post:
https://www.livescience.com/57985-tardigrade-facts.html
https://news.nationalgeographic.com/2017/07/tardigrades-water-bears-extinction-earth-science/
If you read this whole blog post, you are my hero! Thanks for reading. Please feel free to leave me a comment and feedback below. Also, let me know if there is any particular science topic you would like me to look at “through green tinted glasses” and I will write about it.
Life through green tinted glasses 