Earth's hardiest species likely to survive 'until the Sun dies'

Tardigrades or 'water bears' have been described as 'as close to indestructible' as any creature on the planet

Earth's hardiest species likely to survive 'until the Sun dies'

Scanning electron micrograph of an adult water bear (tardigrade), Hypsibius dujardini. by Bob Goldstein & Vicky Madden, UNC Chapel Hill

The 'micro animals' tardigrades - also known as water bears - would survive 'astrophysical catastrophes' that would wipe out other human life on Earth, new research has shown.

Tardigrades - which have a maximum size of 0.5mm - are water-dwellers and can live for up to 60 years.

Research in the past has shown the tiny animals are able to survive extreme conditions - whether that's in space or in the deep sea.

They can also survive for up to 30 years without food or water, making them a particularly hardy life-form.

Researchers from Oxford and Harvard now say the creatures would be able to survive catastrophic events such as an asteroid strike, an exploding star (supernova) in a nearby system, or gamma ray bursts.

The findings of the study have now been published in Scientific Reports.

None of the events - which would wipe out many species on Earth, humans included - would be powerful enough to 'boil off' the planet's oceans.

As a result, the researchers conclude tardigrades will still be around in 'at least' 10 billion years, or until the sun stops shining.

Co-author of the report, Dr David Sloan of Oxford University, explained: "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."

Another co-author, Dr Rafael Alves, argued that the findings open up questions about what other types of life may exist beyond our own planet.

He observed: ‘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?"