Long after we’re gone, ‘space bears’ will remain
Earth’s toughest creature will be alive until the sun finally flickers out, scientists say
The tiny tardigrade has been named the world’s most indestructible species after scientists discovered it is the only creature that will survive until the sun dies.
Although cockroaches are traditionally seen as Earth’s most resilient species, the eight-legged microbeasts are far hardier and will continue to thrive for around 10 billion years, come hell or high water, Oxford University has found.
Tardigrades, which are also known as space bears or moss piglets, are able to survive for up to 30 years without food or water and endure temperature extremes of up to 150 C, the deep sea and the frozen vacuum of space.
Researchers from Oxford and Harvard University found that their astonishing abilities would protect them from calamities that would wipe out all life on Earth. In fact, the only forces capable of harming tardigrades, such as a gigantic asteroid, an exploding star or a deadly gamma-ray burst will not happen before our own sun dies.
Not only does it suggest that tardigrades will survive long after humans have died out, but it gives hope that life could exist on even the most barren and hostile planets.
“Life on this planet can continue long after humans are gone,” said Dr. Rafael Alves Batista, of the Department of Physics at Oxford University.
“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.”
The water-dwelling micro animals can live for up to 60 years, and grow to a maximum size of 0.5 mm. The only real threat to their existence would be from an apocalyptic event that would cause Earth’s oceans to boil away. But the scientists discovered there are only a dozen known asteroids and dwarf planets with enough mass to cause the oceans to boil if they struck the Earth and none are on a collision course with our planet.
Likewise, for an exploding star to boil away the oceans it would have to be 0.14 light years away, but the nearest star to the sun is four light years away.
Destructive explosions of electromagnetic energy known as gamma-ray bursts, which are thought to be caused by neutron stars colliding or the formation of black holes, could also be a threat to the little creatures, but again none could occur close enough to wipe out the species.
The research was published in the Scientific Reports.
If tardigrades are Earth’s most resilient species, who knows what else is out there.