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The Tardigrade: An Inconspicuous Super Creature
This little guy is a Tardigrade. An animal smaller than the head of a pin. Don't underestimate them, though. Tardigrades have been living on this planet than human beings, about 500 million years. They can make a living anywhere on earth, from the peaks of the tallest mountains to the cauldrons of erupting volcanoes, and even in the deep ocean vents at the bottom of the sea. Tardigrades can also survive in the vacuum of outer space. They've survived all the mass extinctions on this planet. A visitor from another world can even think of earth as the planet of the tardigrades, where humans also live.
The tardigrade looks like an eight-legged cross between a bear and a pig, and also known as moss piglet or water bear. However, a tardigrade is in fact a water-dwelling, segmented micro-animal. Normally, this tiny animal swims around on its four pairs of plumped little legs, sucking the juices out of mosses and lichens.
Tardigrades are really small. With the biggest adults reaching just 1.5 millimeters long, it isone of nature’s smallest creatures. Notwithstanding being this tiny, they are fierce! The Tardigrade's mouth contains sharp dagger-like teeth, which are used to spear algae and even other small animals. And, despite their small size, they are tough. Really tough. They can withstand temperatures above the boiling point of water to absolute zero (-273° Celsius). They can also live under pressures which are six times more than those found in the deepest ocean trenches, and can also survive at ionizing radiation at doses which are hundreds times higher more than the lethal dose for human beings, and are the only animal known to survive in outer space.
But what is it that gives these tiny critters their enormous strength?
First of all, tardigrades can morph their form to survive without water. When they are faced with extreme conditions such as extreme dehydration, this animal effectively curls up, and “dies”. It also loses 99% of the body water content, and then enters a state of suspended animation.
When the temperature gets too cold. It'll retract all its legs, shrink down, and shut down all its biological systems until the surrounding condition improves. They are practically indestructible in this state. As a result, they’re capable of surviving in environments that would otherwise kill them. Which makes it the most extreme survivor on the planet.
Tardigrades can even survive scorching 303 °F environments with ease. They can also survive in temperatures as low as -328 °F.
What about lethal radiation?A human being could be 150 miles downwind from a nuclear blast and still get a lethal dose of fallout. That's about 500 Roentgen (the unit used to measure radiation). The indestructible tardigrade has been shown to survive a thousand times that amount (570,000 Roentgen). This small aquatic invertebrate is nearly invincible.
Life in the desert would be no trouble for the tardigrade either. With nothing to drink, most humans would last less than 2 days. But even camels are no match for an incredible tardigrade. A long time ago, a tardigrade was trapped in a museum's specimen of dried moss. It came back to life when scientists added water to the moss, 120 years later.
It seems you can never judge an animal by its soft and squishy looks.
Additionally, their minuscule size works well in their favor, as it can inconspicuously hide them from predators, whilst they thrive hidden in sediments and seas, perfectly unnoticed by potential starving hunters.
Furthermore, and perhaps the most impressive quality yet, is that tardigrades have traveled to space and made it back home, safe and sound. To test their incomparable resilience, K. Ingemar Jonsson, a Swedish researcher, launched them into outer space in 2007. Most of the tardigrades survived the deadly exposure to cosmic rays, while some tardigrades even survived lethal levels of UV radiation. (It is relevant to point out that this exposure, without the respective suits, protection and strict safety measures for such environment, would be dramatically fatal to humans and basically every other organisms on Earth).
Tardigrades have been living longer than any other living organism. They roamed the earth and seas far before humans, and many other species did. They have been in business for half a billion years, and will outlast us. Will tardigrades be the last organisms standing on the earth? Only time will tell.