when revived, but one died 20 days later

It's often said cockroaches could withstand a nuclear explosion, but the tardigrade or 'water bear' just proved to be even more invincible.

Researchers revived two water bears that have been frozen for 30 years and one of them survived.

Not only did the creature survive its icy prison, but it laid 19 eggs – 14 of them successfully hatched.

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It's often said cockroaches could withstand a nuclear explosion, but the tardigrades or 'water bear' just proved to be even more invincible.Researchers revived two water bears that have been frozen for 30 years and one of them survived. Not only did the creature survive its icy prison, but it laid 19 eggs – 14 of them hatched

A team from the National Institute of Polar Research in Tokyo revived the specimens collected 30 years ago in the Antarctic.

'We therefore documented recovery conditions and reproduction immediately following revival of tardigrades retrieved from a frozen moss sample collected in Antarctica in 1983 and stored at −20 °C for 30.5 years,' according to the journal published in ScienceDirect.

'We recorded recovery of two individuals and development of a separate egg of the Antarctic tardigrade providing the longest records of survival for tardigrades as animals or eggs.'

The team pulled samples of moss, containing the water bears, near the Showa Station research base in Antarctica 30 years ago and stored them in the institute's freezer, according toThe Mainichi.

Both samples, SB-1 and SB-2, started moving when they were both defrosted.

'SB-1 first showed slight movement in its 4th pair of legs on the first day after re-hydration,' according to the study.

WHAT ARE TARDIGRADES? Tardigrades, also known as water bears, are some of the most fascinating animals in world because they can live happily in the most extreme conditions. While not the most attractive creatures, the small, segmented animals come in many forms - there are more than 900 species of them - and they're found everywhere in the world, from the highest mountains to the deepest oceans. They have 8 legs (4 pairs) and each leg has 4 to 8 claws that resemble the claws of a bear. Boil the 1mm creatures, freeze them, dry them, expose them to radiation and they're so resilient they'll still be alive 200 years later. Water bears can hack temperatures as low as -457 degrees, heat as high as 357 degrees, and 5,700 grays of radiation, when 10-20 grays would kill humans and most other animals. Tardigrades have been around for 530 million years and outlived the dinosaurs. The animals can also live for a decade without water and even survive in space. Advertisement

'This progressed to twisting of the body from day 5 along with movement in its 1st and 2nd pairs of legs, but the movements remained slow.

'After starting to attempt to lift itself on day 6, SB-1 started to slowly crawl on the agar surface of the culture well on day 9, and started to eat the algal food provided… in the culture plate on day 13.'

It took SB-1 about a week to fully recover, which indicates these creates are able to stop oxidative damage occurring in their bodies, according to Gizmodo.

But these finding also indicate water bears need time to heal any damages that did occur while they are in frozen state, as SB-1 did not eat for the first two weeks.

The team believes that the water bear kept for 30 years survived and its reproductive function was preserved because damage to its cells and genes caused by oxidization was kept to a minimum under the freezing conditions

One of the two did die after 20 days of being defrosted, but the second specimen started reproducing after 23 days.

A group of eggs were also found tangled in the moss, and within six days those hatched.

The team believes that the water bear kept for 30 years survived and its reproductive function was preserved because damage to its cells and genes caused by oxidization was kept to a minimum under the freezing conditions.

The team pulled samples of moss near the Showa Station research base in Antarctica 30 years ago and stored the moss in the institute's freezer, according to The Mainichi .

Megumu Tsujimoto, specially appointed researcher at the National Institute of Polar Research, told The Mainichi , the institute will work on examining damage to the water bear's genes and its recovery functions to find out about the animals' long-term survival mechanism.