No matter what destructive forces nature throws at the pin-head size tardigrade, it will survive until the Sun finally stops shining.
Even astrophysical catastrophes of the magnitude that wiped out the dinosaurs will not stop this marvel from moving around on its eight stumpy legs.
The near indestructibility of the tardigrade – often known as the water bear – has fascinated scientists for years. It can go 30 years without food, endure temperatures way above boiling at 150C and even stay alive in the frozen vacuum of space.
An Oxford University study today reveals that, like the Man of Steel, the microscopic tardigrade has the powers to withstand cataclysmic events that would extinguish all other life on the planet.
Researchers from Oxford and Harvard have studied what impact three of the most destructive events that could befall Earth – an asteroid strike, exploding supernovae and gamma ray bursts – to see how they would threaten the creature and agree the species would survive.
In order to wipe out the tardigrade, the world’s oceans would have to boil, but none of the doomsday scenarios studied by the team have the power to create such catastrophic impacts.
The only known asteroids and dwarf planets in the solar system with enough mass to make the oceans evaporate cannot intercept Earth’s orbit.
Similarly, an exploding star would need to be 0.14 light years away to create the same destructive, sea-boiling energy, but the nearest one is four light years away.
It is a similar story for apocalyptic gamma ray bursts, the brightest electromagnetic events in the universe that help create black holes. Scientists say the likelihood of such an event happening at the critical distance of 40 light years is minor.
While humanity considers itself as the pinnacle of evolution, the humble water bear – creatures that have fossils dating back 530 million years and can exist at Himalayan altitudes of 20,000ft to the ocean floor at 13,000ft – will be here long after we become extinct.
By being such natural survivors, tardigrades also show how alien life on inhospitable planets with poisonous atmospheres and temperature extremes are out there waiting to be discovered.
Dr Rafael Alves Batista, co-author and post-doctoral research associate in the Department of Physics at Oxford University, says: “Without our technology protecting us, humans are a very sensitive species.
“Subtle changes in our environment impact us dramatically.
“There are many more resilient species on Earth. Life on this planet can continue long after humans are gone.
“Tardigrades are as close to indestructible as it gets on Earth, but it is possible that there are other resilient species examples elsewhere in the universe.
“In this context there is a real case for looking for life on Mars and in other areas of the solar system in general. If Tardigrades are Earth’s most resilient species, who knows what else is out there?”
Fellow researcher at the Department of Physics at Oxford University, David Sloan, added: “A lot of previous work has focused on ‘doomsday’ scenarios on Earth — astrophysical events like supernovae that could wipe out the human race.
“Our study instead considered the hardiest species: the tardigrade.
“As we are now entering a stage of astronomy where we have seen exoplanets and are hoping to soon perform spectroscopy, looking for signatures of life, we should try to see just how fragile this hardiest life is.
“To our surprise we found that although nearby supernovae or large asteroid impacts would be catastrophic for people, tardigrades could be unaffected.
“Therefore it seems that life, once it gets going, is hard to wipe out entirely.
“Huge numbers of species, or even entire genera may become extinct, but life as a whole will go on.’
The study appears in Scientific Reports.