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toughest creature on Earth
The toughest creature on earth is likely one that you have never heard of, it’s called a Tardigrade, also commonly referred to as a water bear, or moss piglet. This creature is about .039 of an inch long full when full grown, it's small but tough. Tardigrades live in freshwater or saltwater, and in most other damp areas. You can in fact find them in almost any damp mossy area. Because of their size you will have to look close to see them, but they can be seen with some low level magnification and even the naked eye in perfect conditions.
What caught my attention and made me investigate this creature is an article I read that talked about what they can tolerate, and I was surprised that I had never heard of them. The article was about how the European space agency sent some up on a rocket in 2007, they spent time on the outside of the rocket, exposed to the vacuum of space. They were sent into space again in 2011 to experience the harshness again with close to a 70% survival rate. They were on the outside of the spaceship for 10 days and exposed to the harsh radiation from the sun, with little damage to them.
The trip to space
The European space agency named their program TARDIS. The point of the program was to expose some of the tardigrades to vacuum only and some to a vacuum and extreme radiation from the sun. They dried the creatures out before sending them into space, which puts them in a state where seemingly nothing can harm them. When they brought them back from space, they rehydrate them and they were fine, and even reproduced after the trip. The scientists are still not sure if they can protect themselves from the extreme conditions, or they can repair any damage that may have occurred.Either way it is amazing.
The ultimate survivor
The Tardigrade can survive almost anything. They have gone for decades in tests with no food or water.There is even a report that some were thought to be dried out for close to 100 years and re hydrated and survived. They can survive temps down to near absolute zero, and heat well past the boiling point of water, that is a range of over 700 degrees Fahrenheit.
They can survive pressures from near zero in space, all the way to the extreme pressure at 6 times the pressure at the deepest depths of the ocean. They can also withstand extremely high radiation exposure, over 1000 times the radiation that will kill a person, and when needed can repair their own DNA. Tardigrades are short chunky creatures with 4 pair of legs with claws on their feet.
Small but Tough
Tardigrades were first discovered in the late 1700’s. Since their discovery, there have been over 1000 species of Tardigrades described by scientists. They have been found on every part of the Earth, from the poles to the equator and from the highest mountains to the deepest depths of the oceans.
In the right light they can be seen with the naked eye, but seeing them is made difficult by the fact that they are nearly translucent and are generally only about 1/64 to 1/32 of an inch long.
Small but Tough
Tardigrades have a 5 segmented body, a head and 4 other segments with a pair of legs on each segment with the last pair attached to a segment that is formed by an extension of the spine. This last set of legs is very different in that they face backwards and are used for holding on in back or pulling their body backwards.
They have no single organ to breathe, they breathe through the skin across their entire body. They eat algae and small invertebrates as their source of food.
Tardigrades are born with the same number of cells that they will have as an adult, as they grow their cells increase in size and they shed their outer skin. The females lay their eggs in their old skin after they get rid of it, and then the male fertilizes the eggs.
Because of their ability to adapt to such extreme conditions scientists feel that studying them and finding out how they survive such extremes, could lead to finding way to help treat and possibly cure cancer.
This is an amazing creature, and one that until recently I didn’t know existed. You have probably heard people say that if everything else dies off, the cockroach will inherit the Earth. I think who ever said that had also never heard of Tardigrades.
There are many amazing creature who live on this planet with us, and they do some truly amazing things, this is one of the most amazing.