The only, certain things in life are death and taxes. But, this isn’t necessarily true. Aging and by extension, death is caused at the most fundamental level by cells; within our bodies lose the ability to repair themselves. However, this problem is not present in all species. There are some organisms on this planet, don’t follow the rules that we do and so they are effectively immortal. We used to think that life was finicky, that it would only take hold where it was not too hot, not too cold, not too dark or salty or acidic or radioactive. And whatever you do, don’t forget to add water. We were wrong.

Among the different other species of lifeform, the one which has remarkably endure character is Tardigrade, the toughest organism on Earth. As the hardy tardigrade demonstrates, life can endure conditions that would mean certain death for us humans. But differences between us and life found in even the most extreme environments on our planet are only variations on a single theme, dialects of a single language.

Temperature

<= -273 °C to 150 °C

Pressure 6000 X 760
mm of Hg
Life-Span >= 100 yrs
in some Sp.
Shape Barrel-Shape
Size 0.3 – 0.5 mm

Tardigrades are the most resilient animals in the universe, and there are about thousands of species. These are the phylum of micro animals that are cosmopolitan in the division, the planet from depths of the ocean to jungles to the river to mud volcanoes. You’ve probably not noticed them because they are so small. About the size of a pinpoint. It was first discovered in 1773 and at the time were named water bears; they commonly found in freshwater; so, called water dweller and their movements resemble the gait of a bear.  They are also known as moss piglets. The name tardigrade means slow stepper. The baby tardigrades are born with a full number of cells, rather than undergo cell division they grow as their cells do. It has compound eye-cups and bodies are lined with small hairs to feel the vibrations. They’re famous for their ability to tolerate an extreme environment that would kill other animals of this entire planet. They can withstand, a whole heck of a lot at almost absolute zero (i.e negative 273 degrees Celsius) and on the hot side they can survive over the boiling point of water ( i.e 150 degrees Celsius). During the extremely cold circumstance, they enter the states called cryobiosis. It has developed a peculiar solution to live through a drought. During drought, it undertakes a state called desiccation, in which they shrivel up- losing their body fluid and slows down the metabolism to 0.01 percent of normal.

The prolonged survival of tardigrade is due to the presence of a unique set of protein that they synthesize, tardigrade-specific intrinsically disordered proteins (TDPs). When it completely desiccates, the TDPs vitrify turning the cytoplasmic fluid of cells into glass crystal. Some species of them withstand the pressure that is six thousand times more than the standard pressure at sea level (i.e. thousands of times at the bottom of the Mariana Trench).

Surprisingly It’s the only one and the first animal to survive inside a vacuum, and have even in outer space exposed to both a vacuum (cold-energy and dark-energy) and solar radiation. It can tolerate an extreme amount of radiation due to damage suppressor protein. It can go without eating for 30 years after which they dry out and become dormant and then they can rehydrate by eating something, carry on as if nothing had happened. It is also called extremophiles. It has survived all five mass extinctions. These characters of tardigrades make it immortal and different from other lifeforms.