The most perplexing animals on the Earth are definitely tardigrades. These tiny creatures appear absurdly adorable; they resemble little blimps that stumble around innocuously on short legs. However, they also have a mythical reputation for being the most resilient and unbreakable creatures on Earth. But have you ever asked how they managed to remain alive in space?
Tardigrades' Characteristics As Explained By Experts
Tardigrades have eight stubby legs and a long, chubby body. Although they resemble pigs or bears and are frequently referred to as "water bears," they are closely related to insects and crustaceans.
"Their proportions are a little bit similar to a bear's, and they're cute - at least some of them are cute to some people," said Roger Chang, a Harvard University molecular biologist who studies tardigrades, NBC News reported.
Most tardigrade species are less than half a millimeter in length and resemble dust mites in size. According to Chang, other species are bigger, reaching a maximum height of 1.5 millimeters, or about the size of a sand grain, large enough to be seen with the naked eye.
According to Rutland Herald, experts discovered tardigrades in the fossil record when sophisticated creatures emerged as early as the middle of the Cambrian Period, more than 500 million years ago. There are more than 1,000 different species of tardigrade that may be found everywhere, from the highest mountains to the ocean's depths. For instance, scientists have discovered them in the greatest heights of the Himalayas and at ocean depths of over 10,000 feet, or over two miles, in the Antarctic.
Rutland Herald, citing several studies, mentioned that tardigrades could endure at depths of 15,000 and almost 20,000 feet. For comparison, the maximum depth at which people can submerge themselves without suffering long-term effects from the pressure is roughly 60 feet.
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Tardigrades can enter the abyssopelagic zone, also known as the abyss, just above subaquatic trenches. Those deep depressions in the ocean floor have little visibility, high pressure, and subfreezing temperatures.
Water bears can survive at -328 degrees Fahrenheit, just 100 degrees above the cold of deep interstellar space. On the other extreme, they can endure temperatures up to 300 degrees.
Here's What Makes Tardigrade Indestructible in Space
The indestructibility of the tardigrade is a result of its environmental adaptations, which are unexpected considering where it lives, such as the chilly, moist clumps of moss that dot a garden wall.
However, Science News found that tardigrade's moss-covered housing might dry out frequently during the year. For the majority of living things, drying is rather disastrous. In certain instances, it harms cells like radiation, vacuum, and freezing do.
One effect of drying is the production of significant amounts of peroxides and other reactive oxygen species. The DNA of a cell gets chiseled into little fragments by these harmful chemicals, much like radiation. Cell membranes might wrinkle and fracture as a result of drying. Additionally, it can cause fragile proteins to unfurl, making them as worthless as crumpled paper airplanes. Tardigrades have developed unique defense mechanisms to counteract this sort of harm.
A tardigrade dries up, releasing various odd proteins from its cells that aren't present in other creatures. The proteins are squishy and formless in water. The proteins, however, self-assemble into long, crisscrossing strands that fill the inside of the cell as the water evaporates. The fibers sustain the cell's membranes and proteins, acting like Styrofoam packing peanuts to keep them from rupturing or unfolding.
Rutland Herald said tardigrades enter a state known as cryptobiosis, which allows them to survive in such harsh environments. They must pull in all eight legs and nearly dry out completely. Imagine it being similar to freezing fruit to preserve its freshness. Tardigrades go into this condition when confronted with severe circumstances, like freezing temperature or a lack of water. Water bears may live in these conditions for up to 30 years. Their cells return to normal and resume normal functioning when water is restored to the tardigrade's habitat or when the pressure returns to levels that allow survival.
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